I like thick sliced raw onion on my burgers! So use them as a “bun” if you don’t have any gluten free, grain free rolls laying around? Once I would take a bite I knew all the onion rings would start falling all over the place, so I wrapped a romaine leaf on the outside to hold all the onion rings in place. It worked! The onions also insulated my fingers from the heat of the just cooked burger. I love a good burger, especially one you can pick up and eat. Don’t like the knife and fork approach too much! If you don’t like the raw onion aspect, just use several lettuce leaves to keep the heat from the burger at bay!