We were going to make BLTs last night, but I did not want to make a special trip to the store to get lettuce and tomatoes. We did, however have the necessary makings for a Patty Melt (minus the rye bread) but we did have some really good sandwich bread. I followed this recipe from Bon Appetit, which I slightly modified as Laura does not like the sweetness in the caramelized onions so much. I offset this with a splash of vinegar. BA’s special trick is to smear each slice of bread with mayonnaise instead of butter. The mayo toasts up nice and crisp — good trick!
2 tablespoons vegetable oil
2 large onions, thinly sliced
1 teaspoon cider vinegar
1/4 small onion, finely chopped
1 pound ground beef, 20% fat
1 tablespoon ketchup
1/2 teaspoon garlic powder
1 teaspoon kosher salt
1/4 teaspoon freshly ground black pepper
1 tablespoon vegetable oil
8 slices rye bread
4 ounces sharp cheddar cheese, thinly sliced
4 ounces Swiss cheese, thinly sliced
8 teaspoons mayonnaise
1. FOR ONIONS: Heat oil in a medium skillet over medium heat and cook onions, stirring often and adding water as needed to prevent burning, until deep golden brown and very soft, 20–25 minutes. Add vinegar and stir. Set aside.
2. FOR PATTIES AND ASSEMBLY: Gently mix onion, beef, ketchup, garlic powder, salt, and pepper, in a medium bowl. Divide into 4 portions and press each between 2 pieces of parchment or waxed paper until about ¼” thick (you want them roughly the same dimensions as the bread you’re using.)
3. Heat oil in a large skillet, preferably cast iron, over medium-high heat. Working in 2 batches, cook patties, pressing gently, until browned but still pink in the center, about 2 minutes per side. Transfer to a plate.
4. Wipe out skillet and reduce heat to medium. Top 4 slices of bread with cheddar, then beef patties, caramelized onions, and Swiss cheese. Close up sandwiches and spread each top with 1 tsp. mayonnaise. Place in pan, mayonnaise side down, and weight with a foil-covered heavy pan. Cook until bottom slice is golden brown, about 3 minutes. Remove weighted pan and spread the top of each sandwich with 1 tsp. mayonnaise. Flip and weight again. Cook until other side is golden brown and cheese is melted, about 3 minutes.