Patty Melt Grilled Cheese As seen on Damn Delicious Bookmark recipe Print recipe Download recipe Share Total Time 50 minutes Prep Time 15 minutes Cook Time 35 minutes Rating 0 out of 5 stars (0) Ingredients 8 servings 4 tablespoons unsalted butter, divided2 large onions, thinly sliced2 cloves garlic, minced¼ teaspoon dried thyme1 ½ pounds ground beefKosher salt and freshly ground black pepper, to taste8 slices rye bread4 tablespoons mayonnaise4 ounces sharp cheddar, thinly sliced4 ounces Swiss cheese, thinly sliced Calories AmericanKid-FriendlyDinnerDairyIntermediateQuick and EasyLunchComfort FoodGrillingSavoryCrispyCreamyMeatMain Courses ... How would you rate this recipe? 1 stars 2 stars 3 stars 4 stars 5 stars Preparation Inline ingredients (beta) Cook mode Click to complete Step 1 Preheat a waffle iron to medium-high heat. Lightly oil the top and bottom of the waffle iron or coat with nonstick spray. Step 2 Melt 2 tablespoons butter in a large skillet over medium high heat. Add onions, garlic, and thyme; season with salt and pepper, to taste. Cook, stirring occasionally, until the onions are very soft and caramelized, about 25 minutes; set aside. Step 3 Divide ground beef into 4 balls; press each lightly to form 1/4-inch-thick patties; season with salt and pepper, to taste. Step 4 Melt remaining 2 tablespoons butter in the skillet. Add patties to the skillet and cook until browned and cooked through to medium rare, about 3-4 minutes per side, flipping only once. Step 5 With a butter knife, spread mayonnaise on one side of each slice of bread. Working in batches, place slices, mayonnaise side up, into the waffle iron. Top with patties, onions, cheese, and remaining bread slices, mayonnaise side down. Close gently and cook until golden brown and crisp, about 3-4 minutes. Step 6 Serve immediately.