Stir together the olive oil, red wine vinegar, lemon juice, Italian seasoning, salt and pepper together in a large bowl.

Add the chicken to the bowl and make sure that the chicken breasts are completely covered in the marinade.

Allow the chicken to marinate for at least 30 minutes or overnight.

Then preheat the grill to 350 degrees F. Gently brush the grates of the grill with the oil to prevent the chicken from sticking.

Place the chicken on the grill. Cook for 5-7 minutes per side until the chicken reaches an internal temperature of 165 degrees F.

Flip the chicken breasts again and top each chicken breast with marinara sauce (spoon it on top of the chicken) and the shredded mozzarella cheese.  Close the lid on the grill and allow the cheese to melt.

Then remove the chicken from the grill and let the chicken rest for 5 minutes.

While the chicken is resting, prepare the breadcrumb topping.

Melt the butter in a skillet over medium high heat.  Add in the breadcrumbs and sauté them in the butter until they are golden brown.

Serve the chicken breasts topped with the breadcrumb topping and enjoy!