Garlicky Shrimp Alfredo Bake (Creamy Weeknight Pasta) - Quickie Recipe

Ingredients

• 12 oz (340 g) penne pasta
• 1 lb (450 g) raw large shrimp, peeled and deveined
• 1 teaspoon kosher salt, divided
• 1/2 teaspoon black pepper, divided
• 1 tablespoon olive oil
• 5 cloves garlic, minced
• 2 tablespoons chopped fresh parsley, plus more for serving
• 1 teaspoon lemon zest
• 1 tablespoon fresh lemon juice
• 3 tablespoons (42 g) unsalted butter
• 2 tablespoons all-purpose flour
• 1 1/2 cups (360 ml) whole milk
• 1 cup (240 ml) heavy cream
• 1/2 cup (50 g) freshly grated parmesan cheese, plus 2 tablespoons for topping
• 1 cup (115 g) shredded low-moisture mozzarella cheese, divided
• 1/4 teaspoon red pepper flakes, optional
• 1/3 cup (80 ml) reserved pasta water, plus more as needed