Preheat oven to 180°C (350°F). Wash the 4 turkey schnitzel or chicken breasts, pat dry, and cut into smaller pieces. Coarsely chop the 4 colored peppers and 2 small zucchini. Cut the 3 onions into eighths. Place everything into an ovenproof casserole dish with a lid.
In a bowl, mix 1 glass Cola light (or Coke Zero), 1 packet canned tomatoes, 2 tablespoons tomato paste, 1 tablespoon noble sweet paprika powder, 1 tablespoon curry powder, 1 teaspoon hot paprika powder, 1 teaspoon instant broth, salt, and pepper. Pour this mixture over the turkey and vegetables.
Cover the casserole with the lid and bake for 40 minutes at 180°C (350°F), until the turkey reaches an internal temperature of 74°C (165°F).