7 tbsp. coarse-grained mustard
1/4 c. mayonnaise
1 tbsp. prepared horseradish
3 tbsp. butter
2 tbsp. oil
12 fully cooked bratwurst
4 c. coarsely chopped onions
1 lb. good quality sauerkraut, drained
1 tbsp. caraway seeds
12 lg. poppyseed buns
1 (8 oz.) pkg. sliced Swiss cheese, cut in thin strips
12 lg. squares heavy-duty aluminum foil

Mix mustard, mayonnaise and horseradish in small bowl; reserve. Heat butter and oil in large skillet over medium-high heat. Add bratwurst, cook, turning until evenly browned, about 10 minutes. Remove from pan; reserve. Add onions and sauerkraut to skillet. Cook, stirring occasionally with wooden spoon until lightly browned, about 5 to 6 minutes. Mix in caraway seeds; reserve.

To Assemble: Spread about 1 tablespoon of mustard mixture on cut sides of each bun. Put 1 bratwurst in each bun. Top each with some sauerkraut mixture. Top each with sliced cheese. Lay each prepared bratwurst on top of cut foil. Bring foil up around bun, sealing and rolling to close. Leave some space at top. Do not close too tightly.

Bratwursts can be refrigerated at this point up to 24 hours. Bring back to room temperature before heating. Heat in 400 degrees oven for 10 minutes. Serves 12.