Make the caramelized onions. Thinly slice one whole red or white onion lengthwise. Heat two tablespoons butter in a large pan or skillet over medium heat until melted and bubbling. Gradually add onions, and cook stirring occasionally, until onions are soft. Repeat until all
onion slices have been added. Reduce heat to medium low or low and cook, stirring occasionally, for about 15-20 minutes until onions are super soft and caramelized. They should turn a light to medium brown color. Set aside.

Make the beer cheese sauce. In a small to medium saucepan or pot, melt butter over medium heat. Add flour and whisk or stir frequently for about 3 minutes, until flour and butter have formed thick paste. Add spices and stir to combine. Add beer. Stir until flour mixture is smoothly blended into beer. Add half and half. Continue to whisk until smooth. Reduce heat to low and gradually add shredded cheese, about one cup at a time. Stir until cheese is melted and blended into the sauce, and keep adding cheese until you reach desired thickness. Keep sauce warm, on very low heat while you cook the burgers. Give the sauce a good stir before serving.

Make the brat burger patties. In a large bowl, combine ground pork or beef and all spices. Divide the mixture into four equal portions and then flatten into burger patties using your hands.

Heat your grill to medium high heat. Cook brat burger patties until brown and cooked through, about four minutes per side.

Serve brat burgers on brioche or pretzel buns. Top with caramelized onion and beer cheese sauce.