Ham and Cheese Sliders with Special Sauce

Ingredients for Sliders:

24 small dinner rolls
2/3 cup mayonnaise
24 pieces honey ham, sliced thin
24 small slices Swiss cheese
Ingredients for Poppy Seed Sauce: 
1 Tablespoon poppy seeds
1 1/2 Tablespoons yellow mustard
1/2 cup butter, melted
1 Tablespoon minced onion
1/2 teaspoon Worcestershire sauce

Directions: 

1. Spread mayonnaise onto both sides of the center of each roll. Place a slice of ham and a slice of Swiss inside of each roll. Close rolls and place them into a large baking dish or heavy cookie sheet. Place very close together.
2.  In a medium bowl, whisk together all of the poppy seed sauce ingredients. Pour evenly over all of the sandwiches, using just enough to cover the tops.  May have some sauce left over; if so, use for dipping.  Let sit 10 minutes or until butter sets slightly.
3. Cover with foil and bake at 350 degrees for 12-15 minutes or until cheese is melted. Uncover and cook for 2 additional minutes or until tops are slightly brown and crispy. Serve warm.