Slice the onions thinly and heat olive oil in a large skillet over medium heat. Add onions and cook, stirring frequently until caramelized, about 10-15 minutes.

Push the onions to the side and add ground beef. Cook, breaking apart, until browned, about 5-7 minutes.

Stir in soy sauce, garlic powder, and onion powder. Mix well and cook for an additional 2 minutes.

Sprinkle cheese over the beef mixture and cover. Allow cheese to melt on low heat for 2-3 minutes.

Toast gluten-free buns until golden, then spoon beef and cheese mixture onto each bun.

Serve immediately, optionally garnished with fresh herbs.