2 cups small pasta shells
1/2 pound boneless skinless chicken breasts, cut into 3/4-inch cubes
2 tablespoons olive oil, divided
1 medium onion, chopped
1 medium carrot, finely chopped
1 celery rib, chopped
1 package (12 ounces) frozen fully cooked Italian meatballs, thawed
1 can (10-3/4 ounces) reduced-fat reduced-sodium condensed cream of chicken soup, undiluted
1 package (10 ounces) frozen chopped spinach, thawed and squeezed dry
1 cup reduced-sodium chicken broth
2 teaspoons minced fresh thyme or 1/2 teaspoon dried thyme
1/2 teaspoon salt
1/8 teaspoon pepper
3/4 cup shredded Asiago cheese