Rigatoni with Spicy Calabrese-Style Pork Ragù

INGREDIENTS

• 1 medium onion, quartered
• 1 carrot, peeled, cut into 1-inch pieces
• 1 celery stalk, cut into 1-inch pieces
• 4 garlic cloves
• 2 fresh oregano leaves
• 1/4 crushed red pepper flakes
• 1/2 coarsely chopped flat-leaf parsley, divided
• 1 28-ounce can whole peeled tomatoes
• 1/4 olive oil
• 1 hot or sweet Italian sausage, casings removed
• 1 ground pork
• Kosher salt, freshly ground pepper
• 1 tomato paste
• 1 mezzi rigatoni or penne rigate
• 3/4 finely grated Parmesan or Grana Padano plus more