In a small bowl, stir together the cole slaw mix and the dressing, cover, and chill until needed.
In a frying pan, pepper and fry the bacon until crispy. Wrap in a paper towel and set aside. Pour out all but 1 tablespoon of the bacon fat and add the 2 tablespoons of butter. Melt together over medium low heat and add the onion. Sauté until deep golden browned and softened. Add garlic and sauté one minute longer. Remove from heat, cover and set aside.
Grill or pan-fry steak seasoned with salt and pepper in some butter until desired doneness. Place onto a plate to rest.
While steak is resting, add grated cheese to one of the pans, spread out into a thin layer, and fry until golden brown on the bottom and edges are crispy. Remove with a spatula to a plate.
Butter and toast insides of bun, slice steak thinly against the grain and pile onto bottom of bun. Top with caramelized onions and chopped bacon. Place cheese skirt on top of onions, and spoon slaw on top of cheese. Place on top toasted bun. Take a big bite and enjoy!