To make these Philly Cheesesteak Sliders gluten free, use certified gluten-free slider buns or small gluten-free rolls. Confirm that the Worcestershire sauce and chicken broth are gluten free, as some brands may contain gluten-based additives. Check the mozzarella cheese, sliced mushrooms, seasonings, and any packaged ingredients for gluten or cross-contamination warnings. Use clean utensils, pans, and baking sheets to avoid cross-contact.