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.
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