Preheat oven to 400 degrees F. Combine the yogurt and tomato sauce in a small bowl and set aside. Heat the oil in a large skillet. Season the chicken all over with salt and pepper. Saute chicken, skin-side down first, until golden brown, about 2 minutes per side. Transfer chicken to a casserole, and cover to keep warm.
In the same skillet, saute the onion until soft and clear, about 3 to 5 minutes, then add the garlic paste and the sugar, stir until dissolved. Stir in the paprika, vinegar, and cayenne. Add the yogurt-tomato sauce, and kidney beans. Bring mixture to a boil, then spoon over the chicken.
Transfer casserole to oven and bake about 15 minutes. Serve hot.
c.1997, M.S. Milliken & S. Feniger, all rights reserved