This MeatballSub is filled with juicy, tender homemade meatballs that have been simmered in a delicious marinara sauce, loaded into a toasted bun and topped off with melty Italian cheese.
MEATBALLS: Using the large holes on a cheese grater, finely grate the onion. Add to a large bowl along with the milk, panko, Parmesan cheese, ground beef, minced garlic, dried oregano, fresh parsley, egg, and salt and pepper to taste (I add about 1 teaspoon salt and 1/2 teaspoon freshly cracked pepper). Mix until ingredients are combined. Add in the ground beef and fold with your hands until combined. Handle as little as possible and don't overwork the mixture or the meatballs will be tough.
MEATBALLS, CONTINUED: Measure out about 2 tablespoons of the mixture and gently form a ball. Repeat with all of the meat mixture. You should get around 22-25 meatballs. Make sure they are all about the same size so they'll cook evenly.
COOK: In a large nonstick skillet, add 1 and 1/2 tablespoons olive oil. Heat to medium high and then add in about 1/2 of the meatballs. Gently turn the meatballs over and cook for about 3-5 minutes or until they are browned all over (but not cooked through). Remove to a plate. And another 1 and 1/2 tablespoons oil and repeat with the rest of the meatballs. Remove all meatballs to the plate.
COOK CONTINUED: In the same skillet, add the entire jar of marinara sauce. Return the cooked meatballs to the pan and stir to cover them with the sauce. Cover with a lid and simmer for 8-12 minutes, turning every now and again, or until completely cooked through (food thermometer registers 165 degrees F).
ROLLS: Meanwhile, preheat the oven to 350 degrees F. Cut the rolls in half lengthwise and brush with olive oil. Place on a large tray and bake for 3-5 minutes or until lightly toasted.
ASSEMBLE: Remove subs from the oven and set the oven temperature to high BROIL. Pile meatballs and sauce onto sub rolls -- 3 to 4 meatballs per sandwich. Top with shredded cheese and place under the broiler to melt cheese (watch carefully-- it only takes 1-2 minutes). Top with shredded basil and enjoy hot.