1/3 c. softened butter
1/2 c. minced onion
1/3 c. mustard (of your choice!)
8 hamburger buns, split
16 slices thin, sliced deli ham
8 slices Swiss cheese (or your choice!)
Combine butter, onion, and mustard and spread 1 tbsp. over both bun halves. Layer ham and cheese over bottom halves. Replace tops. Wrap each in foil. Bake at 350 for 6-10 minutes or until cheese melts. You may also freeze these tightly wrapped for up to 2 months. To use frozen sandwiches bake at 350 for 30-35 minutes.
Nice to have for an unexpected guest!