Poulet au Vinaigre

Cut the chicken into pieces. Fry them in the oil in a casserole. When they start to brown, add the chopped shallots; let it blond for 10 minutes, stirring often. Salt, pepper, water with 3 tablespoons of vinegar, cover and continue cooking of the chicken for another 15 minutes. Remove the pieces of chicken, place them on a serving dish, set them back warm. Add the tomato sauce to the cooking juice and the rest of the vinegar, whisk slightly incorporating the butter divided into hazelnuts. Pour this sauce over the chicken and serve.