Primavera Stuffed Chicken

Preheat oven to 400°. Make slits in each chicken breast, being careful not to cut through completely, and stuff with zucchini, tomatoes, bell peppers, and red onion. Drizzle with oil and season with Italian seasoning, salt, and pepper. Sprinkle with mozzarella. Bake until chicken is cooked through and no longer pink inside, 25 minutes. Garnish with parsley before serving.