Butter or lightly grease the bottom of a 13-by-9-inch baking dish.
Without separating into individual rolls, slice the top half of the bread off the bottom.
Spread 1-2 Tbs Terrapin Ridge Farms Onion Blossom Horseradish Dip on open face of the bottom half of the bread. Place the bottom portion of the rolls in the prepared baking dish.
Layer half of the cheese on top of the bottom rolls. Next layer all the roast beef on top. Add the pepperoncini on top. Finally, layer the last half of the cheese on top.
Place the top section of rolls on top of everything.
In a small bowl, combine the completely melted and slightly cooled butter, poppy seeds, minced garlic. Season to taste if desired. Whisk to combine.
Using a pastry brush, liberally brush the butter mixture over the tops and sides of the rolls until well coated. Some of the butter mixture will pool at the bottom of the pan which is fine -- this will help season the bottom section of rolls!
Bake, covered with foil, for 20 minutes. Remove foil and bake for another 3-5 minutes or until cheese is gooey/melty and tops of rolls are slightly crispy (watch carefully).
Remove, cut apart with a serrated knife, and serve while hot!