We had never eaten at a Smashburger restaurant, but tried this one last night. They have Udi's gluten free buns for their burgers, fries fried in a dedicated fryer, and they seemed to know to take all the proper precautions to avoid cross contamination. (They don't toast the GF rolls, since the toaster is used for regular buns). Our Celiac son liked the burger/bun, as well as the thin fries. Just not sure if their ketchup is GF...they have their own brand, and the last ingredient was natural flavor. My son didn't want to bother asking about it, thinking they might not know, so he just happily ate his burger plain. They do have plenty of toppings to choose from if you want a more interesting burger. Check to verify GF status on things like bacon, however. They also offer shakes made with Haagen Daz ice cream, but our son didn't order one.