12 slices cheese (Swiss, Sharp Cheddar, Muenster)
¼ lb. salted butter
1 cup chopped onion
1 cup mustard (I like Dijon)
2 tsp. poppy seeds
12 hamburger buns
Melt butter and sauté chopped onions. Stir in mustard and poppy seeds to blend. Allow mixture to cool slightly. Place ham on bottom piece of bun, cover with cheese slice. Spread top half of bun with 1 spoonful of onion-mustard mixture. Place sandwich halves together and wrap in foil. To serve: Preheat oven to 300 degrees. Place foil-wrapped sandwiches in a single layer on large baking sheet and heat for 20-30 minutes. Sandwiches may be frozen before heating – allow extra 15 minutes to heat frozen sandwiches. Serve warm.
Note: For hors d'oeuvres size or small appetites, make these on Pepperidge Farms Party Rolls. Slice the entire pan of rolls in half horizontally, fill bottom half of rolls in tray with sandwich ingredients, replace top of rolls and slice to divide into individual roll sandwiches. Leave individual sandwiches on tray and wrap tightly in foil. Store in ziploc bags in freezer until ready to bake and serve as directed above.
