Pappardelle with Lamb Ragu

1 medium carrot, finely minced

2 medium celery stalks, finely minced

1/2 small red onion, finely minced

2 pounds boneless lamb (shoulder or leg) cut into 1/2- inch cubes

4 bay leaves

4 whole cloves , wrapped in cheesecloth and tied

1/2 teaspoon freshly ground black pepper , or more to taste

1 cup dry red wine, such as Chianti

1 cup chicken stock or low sodium organic chicken broth

2 cups canned Italian plum tomatoes, preferably San Marzano, with their juice, pureed

1 teaspoon dried thyme

2 tablespoons kosher salt , plus more to taste

1 1/2 pounds pappardelle or dried seminola bucatini

1/2 cup freshly grated Pecorino Romano or Parmigiano-Reggiano cheese