Heat 2 tablespoons of oil in a large skillet over medium heat. Add the onions and sauté until they turn golden brown and caramelized, about 10-15 minutes.

Increase heat slightly, add 1 pound of ground beef, and cook until browned, about 5-7 minutes.

Stir in 2 cloves of garlic and a splash of gluten-free soy sauce, simmering for 2-3 minutes.

Sprinkle 1 cup of shredded cheese over the beef mixture, cover, and reduce heat to low for 3-5 minutes to melt the cheese.

Assemble sandwiches with the beef-onion-cheese mixture in toasted buns and serve hot.