In a skillet, melt 1 tablespoon of butter over medium heat. Add sliced onions and sauté for about 5 minutes until they begin to soften. Pour in the Guinness beer, season with salt and pepper, and simmer for 15-20 minutes until the onions are caramelized and the liquid has reduced.

Cook the Beef Patty

In a bowl, season the ground beef with salt and pepper. Form it into a patty. Heat a grill or skillet over medium-high heat and cook the patty for about 4-5 minutes on each side until it reaches your desired doneness.

Assemble the Patty Melt

Spread minced garlic on one side of each slice of sourdough bread. On the non-garlic side, layer cheddar cheese, cooked patty, Guinness braised onions, chopped bacon, American cheese, and a drizzle of Burger-zing sauce. Top with another slice of bread, garlic side out.

Grill the Sandwich

In the same skillet, melt the remaining tablespoon of butter over medium heat. Place the assembled sandwich in the skillet and grill for about 3-4 minutes on each side until golden brown and the cheese has melted.

Serve

Remove the sandwich from the skillet, slice in half, and serve hot with extra Burger-zing sauce on the side.