To make this Shrimp and Sausage Sheet Pan Bake gluten-free, use certified gluten-free Andouille sausage and Creole seasoning, as some sausage and seasoning blends may contain gluten-based fillers or additives. Confirm that the Italian seasoning, paprika, red pepper flakes, olive oil, and nonstick cooking spray are gluten-free. The shrimp, potatoes, corn, bell peppers, tomatoes, onion, lemon, parsley, and green onions are naturally gluten-free when prepared without gluten-containing additives.