Begin by thinly slicing your onions. Heat a large skillet over medium heat, adding a splash of olive oil, and let it warm. Once hot, add the onions, cooking them slowly for about 20 minutes until golden brown and caramelized.

After the onions are beautifully caramelized, push them to the side and add the ground beef to the center. Break the beef into chunks and cook for about 5-7 minutes, stirring until browned.

Stir in Worcestershire sauce, and season generously with salt and pepper. Allow the mixture to cook together for an additional 2-3 minutes.

Slice your toasted buns in half. Pile the beef and onion filling onto the bottom half of each bun and top with your choice of cheese.

Serve immediately for best experience, ideally with crispy fries or a refreshing side salad.