3 tbl. Unsalted butter, softened
8 slices marble rye bread
4 cooked Cremer’s brat patties
¼ cup mayonnaise
1 tbl. Whole grain mustard
2 tbl. Ketchup
1 tbl. Dill pickle relish
¼ tsp. salt
8 thin slices deli Swiss cheese
1 cup sauerkraut, drained
Adjust oven rack to upper-middle position and heat oven to 400-degrees F. Spread butter on one side of each bread slice. Place bread slices, buttered side down, on baking sheet; set aside.
Whisk mayonnaise, mustard, ketchup, relish, and salt together in a bowl and spread evenly on facing sides of each bread slice. Place 1 slice of cheese on each of 4 bread slices, then layer each with one-quarter of sauerkraut and then top with brat patty, then top with 1 more slice of cheese. Top with remaining 4 bread slices, buttered side up; press down to flatten. Bake until golden brown on both sides and cheese is melted, about 12 minutes, flipping sandwich halfway through baking time. Serve.