Heat two-counts of Olive Oil (to taste) in a large skillet over medium-high heat.
Add the Yellow Onion (1) and cook until soft and translucent, about 3-4 minutes. Add the Garlic (2 clove) and cook until fragrant, about 45 seconds. Sprinkle with Sea Salt (to taste) and Ground Black Pepper (to taste).
Add the Ground Beef (1 pound), crumbling with your cooking tool, and cook until browned and cooked through, about 6-7 minutes. Season once more with Sea Salt (to taste) and Ground Black Pepper (to taste). Drain excess fat if needed.
Add American Cheese Slice (4 slice) to cover the beef. Allow to melt for a minute, then stir to incorporate into the ground beef.
Serve the chopped cheese between toasted Brioche (4) with toppings of choice.