Easy Ham and Cheese Appetizer Sandwiches

Preheat oven to 350 degrees F (175 degrees C).

In a medium bowl, mix together butter, poppy seeds, onion, Worcestershire sauce and prepared Dijon-style mustard.

Slice rolls in half horizontally and set aside tops. Spread bottoms with the butter mixture. Top with ham and Swiss cheese. Replace tops.

Arrange rolls in a single layer in a medium baking dish. Bake in the preheated oven 10 to 12 minutes, until rolls are lightly browned and cheese is melted.