Cook potatoes and puree with the egg and the butter and salt. Courgettes cut into cubes and scatter 2 tbsp flour. After 10 minutes they drain the water and fry in a little sunflower oil, mixed with chopped dill. Separately, fry the onion and to add minced meat (sausage). In a greased baking pan put first courgettes, then minced meat and mashed potatoes on top, grate cheese thoroughly and pour the mixture of milk and cream, seasoned with dill, salt and pepper. Bake 45 minutes at 180 C.