Classic Italian Wedding Soup with Tender Meatballs

Ingredients

• 1/2 cup (45 g) plain breadcrumbs
• 3 tablespoons whole milk
• 8 oz (225 g) ground beef
• 8 oz (225 g) ground pork
• 1 large egg
• 1/2 cup (45 g) freshly grated Parmesan, plus more for serving
• 3 cloves garlic, finely minced
• 1/4 cup chopped fresh parsley
• 1 teaspoon kosher salt
• 1/2 teaspoon black pepper
• 2 tablespoons olive oil, for browning
• 1 tablespoon olive oil
• 1 medium yellow onion, finely chopped
• 2 medium carrots, diced
• 2 celery stalks, diced
• 2 cloves garlic, minced
• 8 cups (1.9 L) low-sodium chicken broth
• 1 Parmesan rind, optional
• 3/4 cup (120 g) acini di pepe pasta
• 5 oz (140 g) chopped escarole or baby spinach
• Salt
• black pepper