Preheat your oven to 350°F (175°C).

Slice the Hawaiian rolls in half horizontally (keep them connected), and place the bottom half in a greased 9x13 inch baking dish.

In a small bowl, mix mayonnaise and Dijon mustard together.

Spread the mayo-mustard mixture on the cut side of the bottom rolls.

Layer the ham, turkey, and Swiss cheese evenly over the rolls.

Add the top half of the rolls and brush the tops with melted butter.

Cover with foil and bake for 10 minutes.

Remove the foil and bake for another 10 minutes, until the cheese is melted and tops are slightly golden.

Optional: Dust with powdered sugar before serving.

Serve warm with raspberry jam on the side for dipping.