Clean, wash and cut the vegetables into large pieces. Peel and roughly chop the onion. Whisk egg yolk, salt, pepper and tarragon. Mix cheese and breadcrumbs. Rinse turkey escalopes cold and dab dry. First turn in the egg yolk, then in the cheese and breadcrumbs mixture. Fry escalopes in hot fat for 12-15 minutes while turning.
Fry the bell pepper, zucchini and onion together in the hot oil. Add stock, stir in tomato paste and braise for about 10 minutes. Add the tomatoes shortly before the end of the cooking time. Season vegetables with salt and pepper. Arrange schnitzel with vegetables on plates. Garnish as desired with fresh tarragon