Preheat oven to 180 ° C.
Season chicken thighs with salt and pepper and fry in a roasting pan on both sides.
Peel onions and garlic and chop finely. Remove chicken thighs, sauté onion and garlic briefly, pour in the tomatoes, season with salt and pepper and simmer 5 minutes.
Put chicken thighs back into the saucepan, add dates, chopped chili pepper and oregano and simmer uncovered about 60 minutes, turning often.