Cut the slider buns lengthwise using a serrated knife and place bottoms on a baking sheet lined with aluminum foil or parchment paper for easy clean up.
In a large skillet over medium high heat, saute the onions and ground beef until the beef is no longer pink and the onions soften.
Stir in the ketchup, mustard, Worcestershire sauce, brown sugar, onion powder, garlic powder, salt, and pepper.
Cook for 2-3 minutes until the sauce is combined with the meat and it starts to thicken. Remove from the heat.
Sprinkle half of the cheese on the slider bun bottoms. Top with sloppy joe mixture evenly between the buns and top with remaining cheese. Add the tops of the buns back.
In a small microwave-safe bowl, melt the butter and add the Italian seasoning.
Brush over the slider bun tops. Sprinkle with the sesame seeds.
Bake for 10-15 minutes until the tops are golden brown and the cheese is melted.
Remove from the oven and serve warm.
Garnish with fresh chopped parsley if desired.
If you've tried this recipe, come back and let us know how it was in the comments or star ratings.