Heat a large skillet or grill pan over medium-high heat. While the skillet heats, mix ground beef with salt and pepper. Make sure not to over-mix, as this can give your burgers a dense texture. Mix just enough to combine, then form them into four equal burger patties.
1 pound ground chuck, ½ teaspoon salt, ½ teaspoon black pepper
Cook burger patties over medium-high heat until one side is seared well, about 3-5 minutes. If the burgers stick when you try to flip them, they're not ready to flip! Allow them to sear another 30 seconds to 1 minute until they come up easily with a spatula.
Flip burgers and sear for another 3-5 minutes, or until the burgers are done to your liking. 3 minutes on each side will cook a medium-rare burger if adding cheese. If you are not adding cheese, cook for 4 minutes instead.
Top the burgers with 2 slices of cheese each and cook about 1 minute until melted. Set the burgers aside to rest for 5-10 minutes.
8 slices smoked Gruyere cheese
Fry eggs in the same pan! No need for butter or oil. The fat from the burgers will keep the pan greased and cook the eggs well. Crack the egg into the skillet and cook until done to your preference. For a runny egg, the white should be completely cooked, but the yolks still liquid.
4 eggs
If you prefer, you can toast buns in the pan, too. After removing the egg, rest the burger buns inside-down in the pan and toast for about 2-3 minutes or until nice and crisp.
4 burger buns
If you're using caramelized onions for your burgers, reheat them over gentle heat on the stove. If you want to caramelize onions at the same time as your burgers, set a separate pan to the side in Step 2 to cook them at the same time.
Prepared caramelized onions
When the eggs are ready, place a burger on each bottom bun. Top with a spoonful of caramelized onions and a fried egg. Place the top buns back on the burger very carefully. Serve with plenty of napkins, and enjoy!