For the chicken in spicy sauce, chop tomatoes, olives and parsley. Heat some oil in a pan, add tomatoes, olives, parsley and spices and let it steam a little.
Season again if necessary and let cool. Roll the chicken pieces in it, put them into a container and pour the rest of the sauce over them.
Cover with lid and let marinate overnight. Place chicken pieces with sauce in a pan with a little butter, cover with lid and let steam until soft.