SAUSAGE AND TORTELLINI SOUP

2 tablespoons EVOO
1 pound bulk sweet Italian sausage
2 large onions, chopped
3 celery ribs with green leafy tops, finely chopped
4 large garlic cloves, chopped
1 small fennel bulb, cored and chopped, a handful of the green fronds reserved
2 large pinches of red pepper flakes
Salt and black pepper
1 28-ounce can diced tomatoes
2 quarts chicken stock
2 9-ounce packages fresh tortellini (cheese, spinach, or mushroom)
1 1/2 cups fresh basil, about 25 leaves, chopped
1/2 cup fresh flat-leaf parsley leaves, chopped
Grated Parmigiano-Reggiano cheese, for passing at the table

Preheat a large soup pot over medium-high heat with 2 tablespoons of the EVOO.  Add the sausage to the hot pot and break it up with a wooden spoon into little pieces as it cooks, 2 to 4 minutes.  Add the onions, celery, garlic, chopped fennel, red pepper flakes, and a little salt and pepper.  Cook, stirring frequently, for 5 minutes.  Add the tomatoes and continue to cook for a minute, then add the chicken stock.  Put a lid on the pot to bring the soup up to a simmer and cook for 10 minutes.  Uncover the pot, add the tortellini, and cook for 5 minutes.  Once the pasta is cooked through, add the basil and parsley, then taste and re-season with a little more salt and pepper if you think it needs it.  Chip up the reserved fennel fronds, stir them in, and serve.  Pass the cheese at the table.