Ultimate Patty Melt with Secret Sauce
•INGREDIENTS: 1 lb ground beef 8 slices of rye bread 8 slices of Swiss cheese 1 large onion, thinly sliced 4 tbsp butter, plus more for spreading Salt and pepper to taste For the Secret Sauce: 1/2 cup mayonnaise 2 tbsp ketchup 1 tbsp relish 1 tsp Worcestershire sauce 1/2 tsp garlic powder 1/2 tsp …