My grandmother made this every Sunday after church for 40 years. Only 3 ingredients and the gravy practically makes itself.

Foil-covered casserole before baking
After 45 minutes, carefully remove the foil (watch for steam). Baste the chicken by spooning some of the developing gravy over the tops of the thighs. Return the dish to the oven, uncovered, and bake for another 25 to 35 minutes, or until the chicken is very tender, the onions are soft, and the sauce is bubbling and slightly thickened.

Check that the chicken is fully cooked: the internal temperature at the thickest part of a thigh (not touching the bone) should reach at least 165°F (74°C), and the juices should run clear when pierced.

Thermometer checking a baked chicken thigh
Thermometer checking a baked chicken thigh
Once done, let the casserole rest for 5 to 10 minutes out of the oven. This short rest allows the gravy to settle and thicken slightly. To serve, use a wooden spoon or large serving spoon to lift a chicken thigh, making sure to scoop up plenty of the onions and silky sauce from underneath.

Variations & Tips
This recipe is intentionally stripped down to three ingredients, but you can adjust it gently without losing its spirit. If you prefer a slightly deeper flavor, you can brown the chicken thighs skin-side down in a skillet for a few minutes before arranging them over the onions; just know that this adds a step and a pan beyond what many grandmothers bothered with. For a different but still classic flavor, swap the cream of mushroom soup for cream of chicken or cream of celery soup.

Chicken thighs browning in a skillet
Chicken thighs browning in a skillet
If your family likes a looser sauce, stir in 1 to 2 tablespoons of water or milk into the soup before spooning it over the chicken; for a thicker, more clingy gravy, simply bake a bit longer uncovered at the end. You can also use a mix of chicken thighs and drumsticks, keeping the total weight about the same; avoid boneless, skinless cuts here, as they won’t give off as much flavor or richness to create that self-made gravy.

For food safety, always keep raw chicken refrigerated until you’re ready to bake, wash your hands and any surfaces or utensils that touched the raw poultry, and use a dedicated cutting board for meat when possible. Make sure the chicken reaches at least 165°F (74°C) in the thickest part, and promptly refrigerate leftovers within 2 hours in a shallow container; reheat thoroughly before serving.