Cut the onions, mushrooms (if needed), carrots, celery and sauté them in a little oil until soft. Add 2 diced tomatoes, spices and then simmer until the tomatoes stew.
Put the vegetables into a lightly greased oven dish, add bay leaf and cover with flour, dissolved in a little water. Sprinkle with chopped parsley, chopped garlic cloves and cover with lemon slices and tomato slices.
Bake in a preheated oven at 392°F (200 °C) for half an hour.