Patty Melt Recipe

Slice onions

Peel and halve the onion, then slice into thin half-moons (about 1/8–1/4 inch thick).

Heat a skillet over medium-low heat and add 1 tablespoon unsalted butter and 1 teaspoon olive oil. When butter is melted and shimmering, add the sliced onions in an even layer.

Season with 1/4 teaspoon salt, 1/4 teaspoon black pepper, and 1/2 teaspoon brown sugar if using. Cook onions slowly, stirring every 2–3 minutes, until they are deeply softened and golden brown — about 20–30 minutes. If they begin to stick, scrape the fond with a wooden spoon and add a splash (1–2 teaspoons) of water.

When onions are richly caramelized, transfer them to a bowl and set aside. Keep skillet handy for cooking patties.

Divide the 1 lb ground beef into 4 equal portions (about 4 oz each) and gently form into thin, slightly oversized patties (they should be slightly larger than your bread slices to account for shrinkage). Do not overwork the meat — press once or twice to form patties about 1/2 inch thick.

Season both sides of each patty with 1 teaspoon Worcestershire sauce, a pinch of kosher salt (about 1/4 teaspoon per patty) and freshly ground black pepper (about 1/8 teaspoon per patty).

Heat the same skillet (or a clean heavy skillet/griddle) over medium-high heat and add 1 tablespoon vegetable oil. When oil is shimmering and just starting to smoke, add the patties. Cook without moving for 2–3 minutes to develop a brown crust.

Flip the patties and immediately top each with a slice of Swiss cheese (and half a slice of American cheese if using). Cook another 1.5–2 minutes, until cheese is melted and patties reach desired doneness (internal about 140–150°F for medium). Remove patties to a plate and tent with foil.

Spread 1/2 teaspoon Dijon mustard and 1/2 teaspoon mayonnaise (if using) on the inside of 8 slices of rye bread.

Butter the outside of each bread slice with softened butter (about 3/4 teaspoon per slice; total about 3 tablespoons).

Place one bread slice, buttered side down, on a clean skillet or griddle over medium heat. Top with a cheese-covered patty, then a generous portion (about 2 tablespoons) of the caramelized onions, then a second slice of Swiss (or American) cheese if desired. Top with the second bread slice, buttered side up.

Cook the sandwich 2–3 minutes per side, pressing gently with a spatula or using a weighted press, until the bread is deep golden brown and the cheese is fully melted. If the bread is browning before the cheese melts, reduce heat to medium-low and cover the pan briefly (30–60 seconds) to encourage melting without burning bread.

Transfer sandwich to a cutting board and let rest 1 minute, then cut in half diagonally. Repeat with remaining sandwiches.

Serve hot. Patty melts pair well with crinkle-cut fries, dill pickles, or a small side salad. Optionally serve with ketchup or extra Dijon for dipping.