Cheesy Chicken and Broccoli Casserole

Ingredients

• 1/2 cup grated Parmesan cheese
• 1 1/2 cups shredded mozzarella, divided
• 1/4 teaspoon black pepper
• 3 cups cooked chopped chicken
• 12 ounces broccoli, coarsely chopped
• 1/4 cup unsalted butter, divided
• 1/2 teaspoon salt
• 1 cup heavy whipping cream
• 2 cloves garlic, minced