Line a baking sheet with parchment paper or foil. Spray very lightly with cooking spray.
In a bowl, mix together butter, sesame seeds, Italian seasoning, parmesan, red pepper flakes and garlic powder.
Use a large serrated knife to slice the rolls in half, separating the tops from the bottoms. Place the bottom of the rolls onto the prepared baking pan.
Brush 1/3 of the butter mixture onto the bottom buns.
Layer on half of the cheese, then all of the pepperoni, salami, the remaining cheese and then the ham.
Place the tops of the rolls onto the sandwiches.
Brush another ⅓ of the butter mixture evenly over the rolls.
Cover the rolls loosely with foil.
Bake in the preheated oven until the rolls are lightly browned and the cheese has melted, about 25 minutes.
Remove the foil and bake for an additional 3-5 minutes or until lightly browned and cheese is melted.
Add the freshly snipped parsley to the leftover butter.
Brush the remaining butter sauce over the rolls.
Slice into individual rolls through the ham and cheese layers to serve immediately with sauce on the side.
*Some brands of Hawaiian rolls are smaller (12 rolls at 12 ounces for the package). We chose rolls that were larger than this (12 rolls at 18 ounces for the package). If you choose smaller rolls, you may have slightly more leftover butter and not need as much meat. The smaller rolls may also bake more quickly so set the timer for 5 minutes less to start.The calories shown are based on the recipe making 12 sandwiches, with 1 serving being 1 sandwich. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information. The information in the nutrition box are calculated through a program and there is room for error. If you need an accurate count, I recommend running the ingredients through your favorite nutrition calculator.**