Mushrooms should be cleaned and washed. Cut into small pieces and sauté with onion, also finely chopped. Mix with cooked rice, the walnuts, flour, tomato paste, bread crumbs and spices. Baking dish or cake pan is greased with sunflower oil, sprinkle with breadcrumbs and pour it into the mixture. The dish is baked in a moderate temperature until browned and crusted.