Pasta e Fagioli recipes

Name: Pasta e Fagioli recipes
Ingredients: 3 tablespoons olive oil, plus more for garnish; 2 ounces pancetta, minced; 1 carrot, peeled and finely chopped; 1 celery stalk, finely chopped; 1 yellow onion, peeled and finely chopped; 2 tablespoons tomato paste; 1 tablespoon minced fresh rosemary; 3 garlic cloves, peeled and thinly sliced; 2 cups dried white beans, soaked overnight; 10 cups chicken stock; 1 cup small pasta shells; 1 tablespoon minced fresh sage leaves, plus whole leaves for garnish; kosher salt; freshly ground black pepper; pecorino romano cheese