► Cut the onions into thin slices and sauté over medium heat in olive oil, on a hot pan.
► Sauté until onions turn golden brown, 10-15 minutes.
► Add salt to taste.
► Mix mayonnaise with chipotle chilies and salt to taste.
► Shape the meat into 8 small patties and fry in olive oil at high heat.
► Season with salt and pepper.
► Top with cheese and let melt.
► Dress the buns with the chipotle mayo, top with lettuce, tomato, sautéed onions, and patties.
► Serve immediately.