Form the Patties: Divide 1 lb. of ground beef into three equal portions, shape into flattened patties that match the size of your rye bread slices.

Season the Patties: Season both sides of each patty with ½ tsp. onion powder, ½ tsp. garlic powder, and salt and pepper to taste.

Cook the Patties: Heat a large skillet over medium-high heat, cook patties for 4-5 minutes per side until browned and cooked through, then set aside.

Mix the Secret Sauce: In a small bowl, combine ¼ cup mayonnaise, 2 tbsp. chopped bacon pieces, 3 tbsp. ketchup, 1 tsp. sugar, and 1 tsp. relish. Stir until well mixed.

Butter the Bread: Spread softened butter on one side of each of the 6 slices of rye bread.

Assemble the Patty Melts: Place 3 slices of buttered bread, buttered side down, in the skillet. Layer 2 slices of provolone cheese, a cooked patty, 2 slices of cheddar cheese, and spread secret sauce on the non-buttered side of the remaining bread slices, then place sauce-side down on the cheddar.

Toast the Bread: Cook over medium heat until the bottom is golden brown and the provolone is melted, about 3-4 minutes.

Flip and Continue Cooking: Flip each patty melt, cook until the other side is golden brown and the cheddar is melted, another 3-4 minutes.

Serve: Let cool slightly on a cutting board before slicing in half, then serve hot with extra secret sauce on the side.