Garlicky Shrimp Alfredo Bake

Ingredients

• 3 tbsp. butter, divided
• Freshly ground black pepper
• 2 tbsp. all-purpose flour
• 1 c. shredded mozzarella, divided
• 3 cloves garlic, minced
• 1 c. chopped tomatoes
• 2 tbsp. freshly chopped parsley, plus more for garnish
• 1/4 c. low-sodium chicken broth
• Kosher salt
• 3/4 c. milk
• 1 lb. raw medium or large shrimp, peeled and deveined
• 12 oz. penne
• 1/4 c. plus 2 tbsp. freshly grated Parmesan, divided