Preheat oven to 350°.
Remove the Hawaiian rolls from the package and cut them in half - without them separating.
Place bottom half of the rolls in a 13x9-inch baking pan.
Top with half of the American cheese, set aside.
In a large skillet, cook the ground beef and onion over medium heat until the meat is no longer pink.
Add can of sloppy joe sauce, soy sauce, and brown sugar to ground beef and continue to heat for another 5 minutes until sauce is completely heated through.
Spoon sloppy joe mixture onto bottom half of the Hawaiian rolls.
Place other half of the American cheese on top of the sloppy joe mixture.
Top with top half of the Hawaiian rolls.
In a small microwave-safe bowl, combine butter, brown sugar, mustard, soy sauce, garlic, sesame seeds, and onion.
Microwave on high for 30 seconds, or until butter has melted. Mix thoroughly.
Use a pastry brush to brush butter mixture onto the top of the sliders.
Bake in oven for 15 - 20 minutes and rolls are golden brown.