Turkey Ragu with Polenta

Name: Turkey Ragu with Polenta
Ingredients: 2 tablespoons extra-virgin olive oil; 4 tablespoons butter; 2 pounds ground turkey; 2 teaspoons poultry seasoning; Salt and freshly ground black pepper; 2 sprigs rosemary, finely chopped; 2 large cloves garlic, finely chopped; 1 onion, finely chopped; 1/2 cup store-bought shredded carrot or 1 small carrot, finely chopped; 2 ribs celery from the heart with leafy greens, finely chopped; 1 fresh bay leaf; 1/4 cup tomato paste; 1/2 cup red wine; 4 cups turkey stock or chicken stock; 1 (28-ounce can) San Marzano tomatoes; 1 cup whole milk; 1 cup quick cooking polenta; 1/3 to 1/2 cup grated Parmigiano-Reggiano, plus some to pass at table; A handful flat-leaf parsley, chopped