Mini Meatball Heroes

INGREDIENTS

• 2 stalks celery, finely chopped
• 1/2 teaspoon freshly ground black pepper
• 1/4 cup chopped fresh Italian parsley leaves
• 6 ounces ground pork
• 1 teaspoon salt
• 2 small onions, finely chopped
• 6 ounces ground beef
• 2 dried bay leaves
• 1/4 cup dried Italian-style bread crumbs
• 12 (3 to 3 1/2-inch diameter) Italian rolls, split, warm
• 1/2 teaspoon sea salt
• 1 large egg
• 2 (32-ounce) cans crushed tomatoes
• 2 carrots, peeled and finely chopped
• 3 tablespoons ketchup
• 6ounces ground veal
• 3 garlic cloves, minced
• 1/3 cup freshly grated Parmesan
• 2/3 cup grated Parmesan
• 1/2 cup extra-virgin olive oil
• Marinara sauce, recipe follows or 26-ounce jar, store-purchased
• 3 ounces sliced provolone
• 2 garlic cloves, finely chopped
• 1 small onion, grated
• 1/3 cup extra-virgin olive oil
• 1/4 teaspoon ground black pepper