Rub the chicken thighs with salt, pepper and spices on both sides.
Transfer the chicken to a deep plate, add more spices and a little sunflower oil. Stir.
Cover the chicken with cling film and refrigerate for 30-40 minutes.
Cut the onion into large half rings.
Cut the potatoes into large wedges. If the potatoes are young, you don't need to peel them.
In a deep bowl, mix onion, potatoes, chicken and sour cream. Salt to taste.
Line a baking tray with parchment paper. Place the chicken and potatoes on top. Bake in the oven for 1 hour at 180⁰С.
When the dish is slightly baked, brush the chicken with the remaining sour cream for a more appetizing crust.
Check the chicken for doneness by piercing it with a skewer. Clear juice from the chicken indicates doneness, but if the juice is pink (with blood), then the roast should simmer in the oven for another 7-10 minutes.