1. Mix ground beef, panko, water, egg, parsley, salt and black pepper in large bowl. Form into 2-inch-meatballs.
2. Heat vegetable oil in large skillet over medium-high heat. Working in batches, fry meatballs until brown all over. Transfer to plate.
3. Pour off drippings from skillet. Reduce heat to medium. Add marinara to the pan. Bring to boil, scraping up the browned bits.
4. Add meatballs back into pan, reduce heat to low. Cover with lid slightly ajar and simmer until meatballs are cooked through, stirring occasionally, about 30 minutes.
5. Split slider buns and place one meatball in each. Top with marinara sauce. Close buns with a party pick.

Photo Credit: Flickr - Cityoen du Monde