Easy Cheesy Pizza Casserole

Ingredients (9)

• 2 teaspoons olive oil
• 1 lb. bulk Italian sausage
• 1 medium yellow onion, chopped
• 1 green pepper, chopped
• 8 ounces white mushrooms, chopped
• 1 1/2 cups low sodium marinara sauce
• 20 pepperoni slices
• 8 slices thick cut garlic bread, sliced into 6 hunks each
• 3 cups shredded mozzarella cheese, divided