01 - Preheat oven to 350°F. Line a baking sheet with parchment paper.
02 - Using a serrated bread knife, slice the entire block of Hawaiian rolls horizontally without separating the rolls.
03 - Place the bottom half of the rolls on the baking sheet and layer cheddar cheese evenly over the surface. Add ham or turkey if using.
04 - Set the top half of the rolls over the cheese and optional fillings.
05 - Combine melted butter with mustard, honey, and garlic powder if desired. Brush this mixture evenly over the tops of the rolls using a pastry brush.
06 - Bake in the preheated oven for 10 to 15 minutes, until cheese is melted and tops are golden brown.
07 - Allow to cool for 2 minutes, slice into individual mini sandwiches, and serve warm.