Step 1

Preheat the oven to 400 degrees F and spray a 9X13 baking pan with non stick cooking spray.

Step 2

Lay the chicken breasts out evenly in the baking pan and top with the onions.

Step 3

Then in a small bowl, stir together the tomato sauce, diced tomatoes, garlic salt, Italian seasoning, salt and pepper.

Step 4

Pour the mixture over the chicken in the baking pan. Then bake it for 25-30 minutes until the chicken reaches an internal temperature of 165 degrees F.

Step 5

Then top with the shredded mozzarella cheese and the sliced pepperonis.

Step 6

Bake for 5 more minutes in the oven to melt the cheese.

Step 7

Let the chicken set for 5-10 minutes and then serve warm. Enjoy!