Meatball and cheese sandwiches

Ingredients:

Meatballs

• 170 g of ground beef
• 170 g of minced veal
• 170 g of minced pork
• 1 small onion, grated
• 1/4 cup chopped fresh parsley (leaves)
• 1 large egg
• 3 tablespoons ketchup
• 3 cloves garlic, crushed
• 1 teaspoon of salt
• 1/4 tsp ground black pepper
• 2/3 tbsp. grated parmesan
• 1/4 cup Italian breadcrumbs
• 1/3 cup extra-virgin olive oil
• Marinara sauce, recipe below, or store-bought sauce (750g jar)

Sandwiches

• 12 Italian rolls, 7-8 cm in diameter, cut in half horizontally and heated
• 1/3 tbsp. grated parmesan
• 80 g provolone slices

Marinara sauce

• 0.5 cups extra-virgin olive oil
• 2 small onions, finely chopped
• 2 cloves garlic, finely chopped
• 2 stalks celery, finely chopped
• 2 carrots, peeled and finely chopped
• 0.5 tsp sea salt
• 0.5 tsp ground black pepper
• 2 cans of 900g canned crushed tomatoes
• 2 dried bay leaves

Preparation:

1. Meatballs:
   
   Combine the first 7 ingredients in a large bowl. Add the cheese and breadcrumbs. Stir in the beef, veal, and pork. Using 2 tablespoons of the mixture at a time, form meatballs 3-4 cm in diameter. Place on a baking sheet.
2. Heat olive oil in a large, heavy-bottomed skillet over medium-high heat. Working in batches, add the meatballs to the skillet and cook until golden brown on all sides, about 5 minutes. Using a slotted spoon, transfer the meatballs to a plate. Drain any excess oil.
3. Return the meatballs to the pan. Add the marinara sauce. Simmer over medium heat until the sauce thickens and the flavors meld, about 10 minutes. Season the sauce with salt and pepper to taste. You can make the meatballs in the sauce the day before, cool them, cover, and refrigerate. Reheat over medium heat before continuing.
4. Sandwiches:
   
   Place the hot meatballs with a little sauce on the bottom halves of the buns. Place half a slice of provolone cheese on top of the meatballs and sprinkle with Parmesan. Spread more sauce on the tops of the buns, cover, and serve.
   
   Culinary advice:
   
   The sandwiches can be assembled and wrapped individually in foil. Reheat the sandwiches in the oven at 175°C for about 15 minutes.
5. Marinara sauce:
   
   Heat the olive oil in a large saucepan over medium heat. Add the onion and garlic and cook until the onion is translucent, about 10 minutes. Add the celery, carrots, and 1/2 teaspoon each of salt and black pepper. Cook until all the vegetables are softened, about 10 minutes. Add the tomatoes and bay leaf and simmer over low heat until the sauce thickens, about 1 hour. Remove and discard the bay leaf. Season with salt and pepper to taste. The sauce can be made up to a day ahead, cooled, covered, and refrigerated. Reheat over medium heat before using.
   Exit: 2 l.