Quarter the potatoes and place them in a 9x13 or other large casserole pan. Drizzle with about a tablespoon of oil, then sprinkle salt and pepper and some thyme leaves to taste, and toss it all together with your hands so potatoes are fully coated. Spread out potatoes in an even layer in the dish.
Slice lemons thinly. Lay about 6-8 lemon slices over the potatoes, and scatter a few thyme sprigs in the pan.
Place chicken thighs on top of lemon slices, then sprinkle with salt and pepper.
Lay remaining lemon slices on top of each chicken thigh and scatter remaining thyme sprigs over chicken. Drizzle chicken with a little more oil if you'd like.
Bake for 35-40 minutes, or until chicken is fully cooked and an instant read thermometer says 165 degrees when inserted into the thickest part of the chicken thigh. Pat yourself on the back and serve!