This easy single layer chocolate cake with chocolate ganache is perfect for weeknights, date nights, birthdays, and small dinner parties. Only one bowl needed and so quick to make – no butter, eggs, or mixer required! This one layer cake can be made in an 8-inch round, 9-inch round, or 8-inch square cake pan, or cut the recipe in half for a 6-inch round cake pan.
Note: this recipe was originally published on February 12, 2018. As of March 2022, I’ve updated: (1) some of the photos, (2) the recipe itself to include a few different cake pan sizes you can use and a couple options for the ganache; and (3) a video. This is still one of my favorite recipes of all time and I hope you love it too! It was the first of my single layer cake recipe series. Check out my single layer carrot cake or my single layer lemon cake for other flavor ideas!
A One Layer Chocolate Cake
True story: I was not planning to share this one layer, small chocolate cake recipe on here. In fact, even after Brian and I made it together for my birthday one weekend, and demolished nearly half of it in 24 hours, I still wasn’t planning to share it.
It’s…simple. Humble. Unassuming. Not really earth shattering – just a good, back-pocket smaller chocolate cake with a tender, light crumb. And chocolate ganache, because chocolate ganache may sound fancy, but it’s actually the easiest thing to make.
We made this cake because I wanted a simple, unfussy cake for my birthday. Brian makes me a homemade birthday cake every year and I try not to make it hard for him. He’s quite good as a baker, actually, but he requires very clear instruction and limited steps, or else he gets nervous. So I don’t like to give him difficult recipes to contend with in hopes he’ll make me cake more often 😉
The problem is that most chocolate cake recipes make a LOT of cake for two people. Not a bad problem to have, some might say. But I saw a challenge: I wanted to create a chocolate cake just as satisfying, just as chocolatey – in smaller portions.
And that was the start of my single layer cake series! It’s an ongoing series of smaller cake recipes that totally deliver on texture and flavor, just in one layer 8 inch or 9 inch proportions.
Origins of the Recipe
This recipe is an adaptation of King Arthur Flour’s “cake pan” cake. Also called wartime cake or wacky cake, it’s an old cake recipe that relies on the reaction generated by combining baking soda (a base) and vinegar (an acid), rather than traditional butter and eggs, to provide the rise and tender crumb we expect from cakes.
The original recipe is mixed AND baked all in an 8 inch square pan, which was exactly the size I was looking for – enough for two people to have cake for a few days, or for a small dinner party. I’d made this recipe a couple times in the past, and remembered liking it – and I knew I could make some tweaks to make it even better.
Why You’ll Love This Single Layer Chocolate Cake
Let’s talk about the amazing properties of this single layer chocolate cake, which I made twice in one weekend with no regrets:
- No butter, no eggs. And you won’t miss them! The good news is that not only is this cake lighter while still having an amazingly fluffy yet dense texture, it’s also a great option for vegans or for those with egg allergies or intolerances. Chocolate cake for everyone!
- No mixer required. Because we’re not creaming butter and sugar and we don’t have to whip in air to create a rise, you don’t need any kind of mixer – just a bowl and a whisk! Speaking of…
- Only one bowl needed! Nope, I’m not kidding. Whisk the dry ingredients together, dump in the wet ones, and stir it all up. Done.
- Takes 45 minutes to make, including bake time!
- Tastes better the second day. This is a cake that only gets better with time. The cake does NOT get dry as long as it’s well-covered, and the chocolate flavor just deepens with a day’s rest. It works around your schedule.
- Chocolate Ganache. Everything is better with ganache on top. And it’s SO EASY. Can you use a microwave? You can make ganache.
What size pan do I need?
You can use an 8-inch round cake pan, 9-inch round cake pan, or 8-inch square cake pan for this single layer chocolate cake. The cake will be taller if you use an 8-inch round or square pan and it will take a few minutes longer to bake (instructions are in the recipe at the bottom of this post). You can also cut the entire recipe in half and bake it in a 6-inch round cake pan for a truly small chocolate cake for two!
I used to prefer using my 9-inch round (the original photos were taken using that pan) but now I like the taller, more generous look of the 8-inch! See what you think!
How to Make Chocolate Ganache
Look how shiny and beautiful that ganache is. If you’ve made ganache before, you know how ridiculously easy it is, despite its fancy name.
If you haven’t made ganache before, here we go:
- Heat heavy cream in the microwave or on the stove until bubbles appear on the edges, just before boiling.
- Pour the hot cream over chopped chocolate or chocolate chips in a bowl.
- Wait 30 seconds.
- Stir, continuously, until a smooth, shiny chocolate pool of happiness is formed, about 30 more seconds.
- DONE. Pour it warm over the cake OR let it cool to room temperature (this takes 1-2 hours) so you can spread it on.
- For WHIPPED chocolate ganache frosting: once cooled to room temperature, use a mixer to beat the ganache on medium to high speed until fluffy and lighter in color. It makes a great chocolate frosting!
FAQs and Recipe Tips
Just use an equal volume of a gluten-free all-purpose flour blend with xanthan gum (I like Bob’s Red Mill Cup for Cup or King Arthur Flour Measure for Measure).
Yes – just use vegan chocolate and use canned coconut cream instead of heavy cream.
This is fine to leave at room temperature for 24 hours, but I would refrigerate it after that for up to 5 days due to the cream in the ganache. The cake itself (unfrosted) is perfectly soft at room temperature for up to a week!
Cut the entire recipe in half and bake in a 6-inch round cake pan for 18-21 minutes at 350 degrees F, or until cake springs back when touched and a tester inserted in the center comes out clean. Works like a charm! You could also bake the full recipe in 2 6-inch cake pans and use whipped ganache (instructions above) or a sturdier buttercream frosting to make a layer cake.
It brings out the deepest chocolate flavor. There’s something about coffee that brings out the flavor of chocolate. Ever had a mocha? You know what I mean. You can use decaf, regular, whatever you want — and if you don’t like coffee, you can use milk or water too. No worries.
This chocolate cake for two may be humble, but it is mighty. It’s just the kind of recipe we all need in our back pocket, whether it be for Valentine’s Day, a loved one’s birthday, or just a Monday. It’s exactly what I wish for you today.
More Single Layer Cake Recipes:
- Single Layer Carrot Cake with Cream Cheese Frosting
- Single Layer Lemon Cake with Lemon Cream Cheese Frosting
- Single Layer Guinness Cake with Irish Cream Frosting
- Snickerdoodle Cake
If you make this single layer chocolate cake, please leave a star rating and a review – it helps others find and enjoy the recipe! You can also tag me on Instagram @katiebirdbakes so I can see what you baked. Thank you!
Single Layer Chocolate Cake with Chocolate Ganache
- 1 8 or 9 inch square or round cake pan
For the cake:
- 1 and 1/2 cups (188g) all-purpose flour
- 1/4 cup (21g) unsweetened cocoa powder (can use natural or Dutch process)
- Scant 1 cup (185g) granulated sugar
- 1/2 teaspoon salt
- 1/2 teaspoon espresso powder (optional; brings out chocolate flavor)
- 1 teaspoon baking soda
- 1 cup (237ml; 227g) brewed coffee (regular or decaf, can be hot or cold)*
- 1/3 cup (78 ml; 67g) olive oil
- 1 teaspoon vanilla extract
- 1 tablespoon apple cider vinegar (or white vinegar)
For the ganache:
- 1/2 cup (118 ml; 113g) heavy cream
- 3/4 cup (4 oz; 127g) chopped dark chocolate or semisweet chocolate chips
For the cake:
- Preheat your oven to 350 degrees F. Grease an 8-inch or 9-inch round cake pan, or an 8-inch square pan. I also like to line the bottom of the pan with parchment paper, to give extra insurance that the cake will come out cleanly. Just trace the bottom of the pan on a sheet of parchment paper and cut it out, then place inside the pan.
- In a large bowl, whisk together dry ingredients: flour, cocoa powder, sugar, salt, espresso powder, and baking soda.
- Pour in the wet ingredients: coffee, olive oil, vanilla, vinegar. Whisk it all together until a smooth batter is formed. You’ll notice it might get a little foamy – that’s the baking soda/vinegar reaction happening. Stop whisking when the mixture is combined and no lumps remain – don’t overmix or the cake will be tough.
- Pour batter into prepared pan, and bake for 28-32 minutes if using a 9-inch round pan, or 32-34 minutes if using an 8-inch round or square pan, until cake springs back when touched and a tester inserted in the center comes out clean.
- Let cake cool in pan on a rack for 10 minutes, then invert the pan onto the rack to release the cake, remove the parchment from the bottom, and flip back right side up onto a cake plate. Let cake cool while you prepare the ganache.
For the ganache:
- In a microwave-safe measuring cup or bowl, heat the heavy cream until bubbling but not boiling, about 30-40 seconds in my microwave. You can also heat it on the stove.
- While the cream is heating, place the chopped chocolate in a medium bowl. Pour the hot cream over the chocolate and let stand for about 30 seconds. Whisk the mixture until a smooth and glossy ganache forms, about 30 seconds.
- You can either pour the warm ganache over the cake immediately, or let ganache sit at room temperature for 1-2 hours and then spread it on the cake. It's delicious either way.
Like this recipe for a small one layer chocolate cake? Please rate it and leave a comment, and sign up for my email list to receive my recipes straight to your inbox every time I post!
Very Nice Valentine Day cake recipe
I absolutely love this recipe! It is not only delicious, but versatile. Today I served it with chopped walnuts and shaved chocolate on top of the ganache, and served drizzled with raspberry sauce. HUGE hit!
Love those additions Pam! Thank you for the review!!
Made this cake on impulse (hubby had a craving) and it came out great! Was out of heavy cream for the ganache, but used evaporated milk with some butter. It worked just fine. It was a breeze baking on just one bowl too! Thanks for sharing this recipe❤️ It will definitely be a staple among my desserts!
Love that!! Thanks Maria!
I do not know what I did wrong but I went over the recipe and I know I followed it to a T. My cake was so dry. I baked it at the lower end of what you suggested. Hmmm disappointed as it was our Christmas dessert by whipped cream helped. The ganache was great though.
Hey Marcia – sorry the cake turned out dry for you. Question: what kind of flour did you use and how did you measure it, i.e. by cups or by weight? Sometimes when flour is measured using cups they can be packed too full, leading to too much flour and therefore a dry cake. I recommend measuring by weight for most accurate results.
Hi Katie. I’ll be driving from NJ to VA and seeing my mother-in-law the next day for her birthday. If I want to make this cake the day before I leave (2 days before I see her, with a day of driving in between), can you think of what I’d physically have to do to make that work? e.g., can’t leave the cake in the pan if I’m going to frost it; but how can I transport it frosted without wrecking it? etc. Thanks for your help.
Hi Michele – apologies for the delay. I think the best way to transport it is in a large and deep tupperware, OR you can leave it in the pan and just put the ganache on top (that is, not down the sides of the cake) and then transport it in the pan. Alternatively, you could transport the cake unfrosted and then quickly make the ganache and pour it over when you’re with her, if that’s a possibility. I hope you enjoy!
Very nice Chocolate cake recipe
It looks amazing . Thank you for sharing this recipe.
Super excited to try it. But I have a question . Can I use butter instead of oil and also can I use whole wheat flour instead of all purpose flour.
If yes please let me know if there are any changes in the quantity while substituting the above 2.
Hi there – yes you can use melted butter instead of oil, and I would recommend using white whole wheat flour as it bakes in a very similar way to all-purpose flour!
Absolutely love the small batch recipe! It comes together very easily and I really appreciate the weight measurements. Cannot believe there are no eggs or butter in this cake, it’s so light, fluffy and chocolatey!
Thank you so much, Christine! I’ve been working on adding weight measurements to all of my recipes because it’s so much more accurate.
I was so happy to find this little cake recipe. I’ve been making a 9×13 size for years, but this, with the ganache, is wonderful!
This cake is marvelous for avoiding food allergies as it works beautifully with wheat-free/ gluten-free flour blends, has no eggs or no dairy, and you can just dust the top lightly with cocoa and it’s also vegan.
So great to hear that GF flour worked for you, Shelly! Thanks for the review!
Amazing recipe and super easy to follow! The coffee definitely made it taste so much better!
Coffee makes all the difference in this cake! Thank you Amaka!
This is the best cake of any kind that I have ever had! I did use 1/2 stick of butter as others did, along with opting for the Dutch chocolate, and it was miraculous! It’s such a deep chocolate taste, so moist and dense, truly a “gourmet” cake. The ganache just topped it beautifully. I would love to try this as a double layer cake but not sure if that’s a good idea. I would love to know your thoughts on that. Thanks for the recipe!
I love this review!! Thank you Dianne! Honestly, I am a little wary of stacking this cake as it’s very soft. I think it might be prone to sagging and/or falling apart if stacked. But, if you try it, please report back!!
Loved this simple cake recipe! Totally delicious; I dusted with powered sugar (didn’t have heavy cream) and it was delicious!
Wonderful! Love that simple pairing!
Will it work to double the recipe? I want to bake it in a 16’” round pan to feed about 14 people. I’ve read that I should reduce each teaspoon baking soda by 1/8 teaspoon. And it will need a longer baking time, but not double the time.
Am I crazy to try this?
It might work, but I haven’t tried it so I can’t be sure – I think you’d be better off using a 9×13 pan if you’re going to attempt it, and just go by when a toothpick comes out clean for when it’s done!
Here is a version for a 9×13 mixed right in the pan I posted many moons ago. It gives it for a wheat free/ gluten free cake, but just sub regular flour and it is delicious.
So glad you posted this recipe! I love it. It is just perfect, not too sweet and not too heavy. It is like a really good entenman’s cake.
Thank you so much Tracey!
If I do not have heavy cream, what can I replace with? Can i replace with coconut cream?
Hi Celia – yes, coconut cream should work!
Thank you so much for this simple yet awesome recipe. The cake was so delectable. The best chocolate recipe ever. I shall be making this regularly now. I baked it for 28 minutes, was out of regular olive oil so used melted butter instead.
Thank you so much! Using butter instead of olive oil is a great idea and probably excellent flavor 🙂
hey i made the cake and after i have poured the ganache on the cake, do i put the cake in the fridge to let it cool or do i just leave it and let it cool on my counter? and if i do leave it in the fridge should i wrap it?
Hi there – yes, you can leave it cool on the counter and store at room temperature for up to a day. Or put it in the fridge, covered, and it will keep for several days. Enjoy!
This is the first cake I ever made and it is AMAZING! So easy, so delicious. Thank you so much! One question – can I substitute coffee with orange juice and make it into a chocolate orange cake? Not sure if the substitution will affect consistency?
Hi Siya! So glad you enjoyed this recipe and congratulations on making your first cake! Adding orange juice would make the cake a lot sweeter, but I think it would work. Let me know if you try it!
I’m so glad you did decide to post this. It is my new favorite chocolate cake. It is the perfect simple chocolate cake. It is the perfect texture and it’s not too sweet. It’s perfectly satisfying. I’ve been making one a week !!
YAY! Thank you so much – so glad you enjoy it! One of my favorites.
Sometimes I’m just craving chocolate, and this recipe is both quick and simple to make, and doesn’t require eggs, which we don’t always have. I’m about to make my third one!
I just put a simple vanilla frosting on top, but it tastes so good… thanks for the recipe!
Yay! So glad you are enjoying it! Thank you!
I love dark chocolate cake and coming across your recipe was a blessing! I made this and was so satisfied with the result. Some changes I did was used butter (i run out of oil), and added only 3/4 cup of sugar. Opted for 8″ square pan and baked it for exactly 34 mins. Came out perfect! Moist, soft cake and it’s day 2 now and the choco flavor is deep! For the ganache, i used half 100% cacao unsweetened & half 60% bittersweet chocolate. Thank you for sharing us your baking expertise, I am a fan.
Thank you so much for this amazing review, Jolina! So glad you loved this recipe 🙂
I made this today. While it was baking I suddenly realized I had mistakingly used baking powder instead of baking soda. It came out fine despite that! The came still rose nicely and had a nice texture. The only other change I made was to use evaporated milk instead of the cream for the ganache because that was all I had on hand. That also came out fine.
I will definitely make this again.
Yay! Thank you so much, Elle – glad it still worked despite the changes 🙂
I tried with measure-for-measure gluten-free all purpose flour for my mom with Celiac disease and it turned out great! I served it with some homemade whipped cream on the side, and my mom said it reminded her of old-fashioned snack cakes like Ho Ho’s or Hostess cupcakes. Will definitely make it again!
Yay! Thank you so much for letting me know about the GF flour – so glad you mom enjoyed it!
Please share whether 1 cup coffee details..As in what goes into it ??
What is shelf life of choclate cake filled and coated with chocolate ganache.
In fridge too
Hi Pooja – it lasts about 4 days on the counter, well-wrapped in plastic wrap or foil. In the fridge it would last about a week!
Can I bake this in an 8″ round pan to get a taller cake?. I ll have to alter the baking time too I guess .
Hi Sharmila, I have not tried this in a 8″ round pan, but if you look at this pan conversion chart from the Joy of Baking, it seems you will be ok if your 8″ round pan has at least 2 inch high sides. You’re looking for the volume to be equivalent to a 9″ round pan (which is why an 8″ SQUARE pan works here too – the volume is the same). I would increase the baking time to 34-36 minutes, for both an 8″ square and an 8″ round. Let me know if you try it!
I made this cake for today…Christmas. Simply amazing! I did only bake my for 20 minutes and it was perfect. I also made it into a Turtle Chocolate Cake by adding my homemade Bourbon Caramel and Pecans. Simply DECADENT! This will be my go to recipe. Thanks for sharing.
Thank you so much for the wonderful review, Jesse! So glad it worked for you. Merry Christmas!
This cake is amazing! My parents absolutely LOVED IT! <3
I think it was delicious and I will use your recipes in the future. Thx Katie! ^_^
Yay! Thanks Sophia, so glad you and your parents enjoyed it.
We just shared this fantastic cake on our blog too! Such a terrific little number and one I go back to often. Guess us Chicagoans think alike!
We sure do! King Arthur Flour is the best!
So amazing!! Great job, Katie! We made with milk and it came out really good!!
Thank you so much Emily! I’m so glad it came out well for you. It’s one of my favorites.
This is A-MAZ-ING!!!!!!!!!!!!! We felt like we were having dessert at a high end restaurant. Kudos to you and King Arthur Flour for this terrific recipe.