Pasta with Salumi Bolognese

Name: Pasta with Salumi Bolognese
Ingredients: 4 ounces mixed salumi (such as soppressata or finocchiona), chopped; 1 tablespoon extra virgin olive oil, plus more as needed; 2 ounces country ham or prosciutto ends, cut into small cubes; 8 ounces ground beef chuck; 1 ounce guanciale or pancetta, cut into small cubes; 2 tablespoons fennel seed; 1 large pinch chile flakes; 1/2 cup diced carrots; 1/2 cup diced celery; 1 cup diced onion; 1/2 cup tomato paste; 2 cups dry red wine; 1 (28-ounce) can tomatoes (whole, peeled), crushed by hand; 1 tablespoon dried oregano, plus more for garnish; 2 cups chicken stock; 4 tablespoons butter, cubed; 2 tablespoons red wine vinegar; 2 pounds dried spaghetti; Chopped fresh parsley; Fresh ricotta (optional)