Preheat oven to 350°F. Grease a 9x13 baking dish or 1/2 steam table foil pan.
Cut the entire pack of hawaiian rolls in half, horizontally (keeping all top and bottom halves separately in tact).
Place the bottom of the rolls into the prepared baking dish.
Distribute the turkey and cheese evenly over the rolls. I like to do a thin layer of cheese on the bottom, with the turkey in the center, and then a layer of cheese on top of the turkey. Place the tops on the rolls. Set aside.
In a medium sized microwave safe bowl, melt butter. Whisk in mustard, brown sugar, worcestershire sauce, onion powder and salt.
Pour sauce evenly over all of the sandwiches. Sprinkle tops with everything bagel seasoning.
Cover with foil and bake for 15 minutes, or until cheese is melted. Uncover and cook for 2 additional minutes. Serve hot.