Spaghetti and Meatballs

INGREDIENTS

• 3 cups torn day-old Italian bread
• 1/2 cup extra-virgin olive oil
• 1 1/2 pounds ground beef (not lean)
• 1/4 cup finely chopped oregano or 1 teaspoon dried, crumbled
• 2 pounds dried spaghetti
• 2 medium onions, finely chopped
• 6 large eggs
• 3 cups whole milk
• 6 (28-ounce) cans whole tomatoes in juice (preferably San Marzano)
• 2 medium onions, chopped
• 1 cup olive or vegetable oil
• 1 tablespoon grated lemon zest
• 1 1/2 pounds ground pork
• Accompaniment: grated Parmigiano-Reggiano
• 2 cups grated Parmigiano-Reggiano (1/4 pound)
• 6 garlic cloves, finely chopped
• 10 garlic cloves, finely chopped
• 1 1/2 pounds ground veal
• 1/3 cup finely chopped flat-leaf parsley
• 1/4 cup extra-virgin olive oil