01 -
In a small bowl, combine mayonnaise, ketchup, Dijon mustard, pickles or relish, garlic powder, smoked paprika, salt, and black pepper. Mix thoroughly and refrigerate until ready to use.
02 -
Heat 2 tablespoons butter over medium heat in a skillet. Add sliced onions and sauté, stirring frequently, until deeply caramelized and golden brown, about 8 to 10 minutes. Remove onions from the skillet and set aside.
03 -
Divide ground beef into four equal portions and shape into balls. Heat a skillet or griddle over medium-high heat. Place each beef ball onto the hot surface, press flat with a metal spatula, and season with salt and black pepper. Cook for 2 to 3 minutes per side until browned and edges are crisp.
04 -
Butter one side of each bread slice. Arrange four slices, buttered side down, on a clean surface. Spread a layer of Signature Sauce on each slice. Top with a slice of cheese, a cooked beef patty, an even layer of caramelized onions, another slice of cheese, and cover with a second slice of bread, buttered side up.
05 -
Heat a skillet or griddle over medium heat. Place assembled sandwiches onto the skillet and cook for 3 to 4 minutes on each side, pressing gently, until bread is golden brown and cheese has melted completely.
06 -
Slice each melt in half and serve immediately with additional Signature Sauce or pickles on the side.