Patty Melt with Caramelized Onions

There's something about the smell of caramelizing onions that makes my entire apartment feel like a cozy diner on a rainy Tuesday. I stumbled upon patty melts accidentally during college when I was too broke for restaurant meals but craving something more exciting than a basic burger. The first attempt was a mess with cheese everywhere, but that first bite of crispy bread and sweet onions made all the cleanup worth it. Now it's my go-to comfort food when I want something that feels indulgent but still comes together in under an hour.

My dad came over during a particularly rough week last winter and I made these for lunch. He took one bite, got that quiet look people get when food reminds them of something good, and said this was better than the diner version he'd been going to for thirty years. We sat at the counter eating them in comfortable silence, just the sound of crunching bread and the rain against the window.

Ingredients

• 500 g (1.1 lbs) ground beef (80/20 blend recommended): The extra fat content keeps the patties juicy and helps them cook up with that crispy edge diners do so well
• 1/2 tsp salt and 1/2 tsp black pepper: Simple seasoning lets the beef flavor shine while the onions and cheese provide the complexity
• 2 large yellow onions, thinly sliced: Yellow onions sweeten beautifully when cooked low and slow, becoming almost like onion jam
• 2 tbsp unsalted butter and 1 tsp sugar: The butter helps the onions cook down evenly while the sugar encourages that gorgeous caramelization
• 8 slices rye bread or sourdough: Rye has that classic diner flavor but sourdough adds a subtle tang that cuts through the richness
• 8 slices Swiss cheese: Swiss melts beautifully and has a nutty flavor that pairs perfectly with caramelized onions
• 4 tbsp unsalted butter, softened: Room temperature butter spreads evenly so every inch of bread gets golden and crispy

Instructions

Caramelize the onions low and slow:

Melt 2 tablespoons butter in a large skillet over medium-low heat and add the sliced onions with the sugar. Cook them for 20 to 25 minutes, stirring occasionally, until they're a deep golden brown and smell incredibly sweet. Set them aside while you make the patties.

Shape and season the beef patties:

While the onions cook, season the ground beef with salt and pepper and form it into 4 thin oval patties that match the shape of your bread slices. Don't overwork the meat just press them gently into shape.

Sear the patties until browned:

Cook the patties in a separate skillet over medium-high heat for 2 to 3 minutes per side until they develop a nice crust and are just cooked through. Remove them from the pan and set aside on a plate.

Butter your bread generously:

Spread softened butter on one side of each bread slice. If you're feeling adventurous, spread Dijon mustard or mayonnaise on the unbuttered side for an extra layer of flavor.

Build your sandwiches:

Layer one slice of cheese, a beef patty, a generous heap of caramelized onions, and another slice of cheese on four of the bread slices (unbuttered side up). Top with the remaining bread, buttered side facing outward.

Griddle until golden and melted:

Cook each sandwich in a clean skillet over medium heat for 2 to 3 minutes per side, pressing gently with your spatula. Flip once when the bread is golden brown and crispy, and cook until the cheese is completely melted.

Rest and serve hot:

Let the sandwiches rest for 1 to 2 minutes so the cheese sets slightly, then slice them in half diagonally. Serve immediately while the bread is still crispy and the cheese is hot.

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These became a Friday tradition during my first year of teaching. A few colleagues would come over, we'd drink cheap wine, and I'd make a big batch of patty melts while catching up about our weeks. Something about the combination of stress relief and comfort food made those evenings feel like exactly what we needed.

Bread Choices That Work

Rye bread is traditional and gives you that authentic diner flavor, especially when it has caraway seeds. Sourdough creates a sturdier sandwich with a tangy flavor that cuts through the rich beef and cheese. I've even used marble rye when I want something that looks impressive on the plate.

Make-Ahead Strategy

The onions can be made up to three days ahead and stored in the refrigerator. They actually develop deeper flavor after sitting overnight. You can also form and refrigerate the patties earlier in the day, just let them sit at room temperature for 15 minutes before cooking.

Serving Suggestions

A simple green salad with acidic vinaigrette helps cut through the richness of the sandwich. Homemade pickles add crunch and brightness that balances the melted cheese. Don't forget extra napkins because these get gloriously messy.

• Coleslaw makes a great side and adds a nice cold contrast to the hot sandwich
• Tomato soup transforms this from lunch into a full comfort meal
• Thinly sliced pickled red onions on top add an extra pop of acidity

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Hope these patty melts become your new comfort food favorite. There's nothing quite like that first crispy, cheesy, onion-sweet bite.

Recipe FAQs

→ What bread works best for a patty melt?

Rye bread is traditional and provides excellent flavor, but sourdough works equally well. Both types hold up well to grilling and complement the beef and onions. Avoid soft white bread as it may become soggy.

→ Why use 80/20 ground beef?

The 80/20 blend (80% lean meat, 20% fat) provides the ideal balance of flavor and moisture. The higher fat content keeps the patties juicy during cooking and prevents them from becoming dry or tough.

→ How do I get perfectly caramelized onions?

Cook sliced onions over medium-low heat with butter and a pinch of sugar. Stir often and be patient—it takes 20-25 minutes for onions to develop that deep golden color and sweet flavor. Rushing this step will result in cooked but not caramelized onions.

→ Can I use different cheese?

Absolutely! While Swiss cheese is traditional, cheddar, American, provolone, or gruyere all work beautifully. Choose a cheese that melts well and complements the beef and onion flavors.

→ What should I serve with patty melts?

Classic diner sides like French fries, onion rings, or potato chips pair perfectly. A crisp pickle or simple coleslaw helps cut through the richness. A side salad also makes a nice light accompaniment.

→ Can I make these ahead?

You can caramelize the onions and cook the beef patties up to a day in advance. Store them separately in the refrigerator. Assemble and grill the sandwiches just before serving for the best texture and flavor.