To make this recipe gluten free, replace the Panko breadcrumbs with certified gluten-free Panko or gluten-free breadcrumbs. Substitute the flour with a gluten-free all-purpose flour blend that is suitable for coating. Also check the Worcestershire sauce label carefully, as some brands may contain gluten. Be sure that all packaged ingredients, including cooking spray and Parmesan if pre-grated, are certified gluten free to avoid any hidden sources.