Baked Ham and Swiss Sammies

"These were so delicious!  I found this recipe on pinterest.  The recipe came from The Kitchen Life of a Navy Wife and the original is from the  King's Hawaiian website.  I only changed two ingredients...instead of Dijon I used regular mustard and I omitted the poppy seeds.  I also changed the baking directions because the time and temp didn't seem adequate.  My baking directions change is included."

INGREDIENTS:

1 12 pack of King's Hawaiian Original Rolls
1 lb. deli ham, shaved
1 lb. Swiss cheese, thinly sliced
1 1/2 sticks butter
3 tablespoons Dijon mustard
1 1/2 teaspoons Worcestershire sauce
3 teaspoons of poppy seeds
1 onion, chopped

Directions

1. Heat oven to 400. Melt butter and mix in mustard, Worcestershire sauce, onion and poppy seed. Simmer until sauce becomes syrupy.

2. Cut the entire pack of rolls in half, horizontally (keeping all top and bottom halves in tact).

3. In a greased 9x13 pan, place bottom half of rolls and spoon 1/3 of the onion mixture over the bottom of the rolls followed by the ham and cheese.

4. Replace the tops of the rolls and spoon the remaining onion mixture over top.

5. Cover and bake for 30 minutes (taking foil off for the last 8 minutes.

Serves 4