Preheat oven to 400 degrees F. Prepare a baking sheet with non stick cooking spray and set aside.
Place beef with onion powder, garlic powder bread crumbs, egg, parmesan cheese, salt, Italian seasoning, and 2 tablespoons of marinara into a large mixing bowl. Mix until combined.
Form balls and place it on prepared baking sheet. Depending on the size you should come out with 12 meatballs. One for each slider. Bake for 15-20 minutes or until meatballs are cooked through.
Place each meatball on a slider and into a casserole dish. Top with a spoonful of marinara sauce and a sprinkle of mozzarella cheese. Bush the tops with olive oil then sprinkle with dried oregano and additional garlic powder.
Bake for an additional 5 minutes until cheese is melted and bread has started to brown. Serve warm and enjoy.