# What You Need:
→ Beef Patties
01 - 1.1 lbs ground beef (80/20 blend recommended)
02 - 1/2 tsp salt
03 - 1/2 tsp black pepper
→ Caramelized Onions
04 - 2 large yellow onions, thinly sliced
05 - 2 tbsp unsalted butter
06 - 1 tsp sugar
→ Sandwich Assembly
07 - 8 slices rye bread or sourdough
08 - 8 slices Swiss cheese (or American cheese)
09 - 4 tbsp unsalted butter, softened
→ Optional Condiments
10 - 1 tbsp Dijon mustard
11 - 1 tbsp mayonnaise
# How To Make It:
01 - In a large skillet over medium-low heat, melt 2 tbsp butter. Add sliced onions and sugar. Cook, stirring often, until onions are deeply golden and caramelized, about 20–25 minutes. Set aside.
02 - While onions cook, season ground beef with salt and pepper. Shape into 4 thin oval patties, roughly the size and shape of your bread slices.
03 - In a separate skillet or grill pan over medium-high heat, cook the patties for 2–3 minutes per side, until browned and just cooked through. Remove from heat.
04 - Lay out 8 slices of bread. Spread a thin layer of butter on one side of each slice. If desired, spread Dijon mustard or mayonnaise on the unbuttered side.
05 - On 4 slices (unbuttered side up), layer 1 slice of cheese, a beef patty, a generous spoonful of caramelized onions, and another slice of cheese. Top with remaining bread, buttered side facing out.
06 - Heat a clean skillet or griddle over medium heat. Cook sandwiches 2–3 minutes per side, pressing gently, until the bread is golden and cheese is melted.
07 - Remove, let rest for 1–2 minutes, then slice in half and serve hot.
