Heat the butter or oil in a frying pan over medium heat. Cook the beef patty until it's browned and cooked through.
1 tablespoon butter, 1 beef patty
In the same pan, fry the egg until the whites are set and the yolk is still runny.
1 egg
Assemble the burger: Spread mayonnaise on the bottom half of the bun, then add lettuce, tomato, the beef patty, cheese, and the fried egg. Top with the other half of the bun.
1 slice cheese, 1 leaf lettuce, 1 slice tomato, 1 tablespoon mayonnaise, Salt and pepper to taste
Serve immediately.
Notes
Add bacon or avocado for extra indulgence.
Use a whole grain bun for a healthier option.