I start by splitting the hoagie buns and melting one tablespoon of butter in a skillet. Then I toast the inside cut-sides until golden. This step gives crunch and structure so the bun doesn’t get soggy later.
Using the same pan (with remaining butter), I cook the thin onion slices over medium heat for about 6–8 minutes until softened and translucent. Then I set them aside while I move on to the beef.
Next, I season the ground beef with salt, pepper, and garlic powder, and shape it into a loose patty. I cook it 5–6 minutes on one side, flip, and cook another 4–5 minutes. Then I return the onions to the pan and use a firm spatula to chop the meat and onion mixture together until they form bite-sized crumbles.
Once the beef is fully cooked, I divide the mixture into four portions (still in the pan). I place 1–2 slices of American cheese on each portion and allow it to melt until it’s gooey and cohesive.
With the toasted buns open, I spread mayonnaise on one side, ketchup on the other (if using). Then I spoon the cheesy beef mixture onto each bun and top with crisp lettuce and juicy tomato slices. It’s best eaten immediately while hot.