Oven Ham Sammies

I've made a loaf version of this type of thing before, but this was definitely easier and I really liked the taste of using the King Hawaiian Rolls. They are a cinch to prepare, can be made ahead of time and I would probably double the recipe next time because everybody loved them!

Oven Ham Sammies
adapted from tasty kitchen

8 oz deli ham
6 slices swiss cheese
1 package King Hawaiian Rolls (12 count)
5 T melted butter
2 T finely chopped onion
1 t poppy seeds
1 t ground mustard

Slice rolls.
Fold one piece of ham and place inside roll. Top with half a slice of cheese and replace top of roll. Continue with rest of rolls.
Mix remaining ingredients and spoon over sandwiches.
Let set for 30 min - overnight.
Bake at 350 degrees for 15.