Braised Pork Shoulder with Polenta

Name: Braised Pork Shoulder with Polenta
Ingredients: 1 boneless pork shoulder, about 3 to 4 lb. (1.5 to 2 kg), cut into 1 1/2-inch (4-cm) cubes; Salt and freshly ground pepper, to taste; Fennel pollen or ground fennel seed, to taste; All-purpose flour as needed; 1 cup (8 fl. oz./250 ml) vegetable oil or lard; 1 yellow onion, finely diced; 1 carrot, peeled and finely diced; 2 celery stalks, finely diced; 1/4 fennel bulb, finely diced; 3 whole garlic cloves; 1 cup (8 fl. oz./250 ml) dry white wine; 1 can (14 oz./440 g) whole plum tomatoes, preferably San Marzano; 8 green Friggitello peppers, stemmed, seeded and quartered; 8 red Nardello peppers, stemmed, seeded and quartered; 12 fresh sage leaves plus 1 Tbs. chopped fresh sage; 2 tsp. chopped fresh rosemary; 1 to 2 quarts (1 to 2 l) pork or chicken broth