Preheat oven to 350 degrees F.
Cook the ground beef and onion until the beef is cooked through. Drain the excess fat.
Add the Manwich sauce and let it cook for 5 minutes.
Cut the Hawaiian rolls horizontally and remove the top part of the rolls. Place the bottom rolls into a 9x13 pan.
Spoon the beef mixture onto the Hawaiian rolls. Top the beef mixture with the cheddar cheese sliced, then put the tops of the rolls back on.
Spray the roll tops with olive oil then top with sesame seeds.
Bake the sliders 10 minutes or until they're heated through and the cheese is melted.