Peel the onion and chop finely. Clean the peppers, remove seeds and cut into strips. Wash the eggplant, remove the stalk and cut this vegetable into slices. Wash the tomatoes and cut into slices. Wash the zucchini and cut into slices. Cut the slices again if necessary. Heat the butter and braise the vegetables for about 10 minutes until al dente. Season the ratatouille with salt, pepper, chopped chervil and parsley. Serve the ratatouille with e.g. boiled rice and fried chicken or as a hot lunch with a piece of baguette.