In a saucepan add the sugar, cayenne pepper, and water, mix with your finger just to mix. In medium heat, boil the sauce without mixing until large bubbles have risen. Add the whiskey and mix for more than 2 minutes, then add the butter until it melts, and then reserves the sauce in a bowl.
Add salt and pepper to the ground beef to taste and mix well. Format the burgers with 150g each.
In a frypan at medium heat, add the bacon and grill until well cooked. Remove and mix it into the sauce
In the same fry pan with the bacon fat, grill the burger for 1 minute, turn, and leave for more than 2 minutes. Flip again and add the cheese. Cover the pan with a lid until the cheese is melty. Remove the burgers and leave on a plate to rest for a few minutes.
Assemble topping the bun with the burger, pour the sauce over it and top with lettuce.