I found this recipe while browsing Pinterest on the internet. If you haven't discovered this site you have to check it out!! I made them for a girl's night earlier this week and they were a hit.
1 pkg. of 12 Hawaiian sweet rolls
1 onion (or 1 tsp onion powder)
1 stick of butter
3 Tbsp. Dijon mustard
2 tsp. Worcestershire sauce
2 tsp. poppy seeds
1/2 lb. shaved ham
8 slices of Swiss cheese
Melt butter in microwave. Add onion (or onion powder), mustard, Worcestershire, and seeds. Mix thoroughly and set aside. Slice rolls in half and place bottoms in an aluminum foil lined 9x13 pan. Spread 3/4 of butter mixture on rolls, followed by ham and cheese. Top with the roll tops. Spread remaining butter mixture over tops of sandwiches. Cover with aluminum foil and bake at 350 degrees for 20 minutes.
Source: Pinterest, Beyer Beware blog