1 (10.75 ounce) can Campbell's(r) Healthy Request(r) Condensed Cream of Celery Soup
1/2 cup plain low-fat yogurt
1/4 cup water
2 tablespoons Dijon-style mustard
1 tablespoon vinegar
1/8 teaspoon ground black pepper
4 cups corkscrew-shaped pasta, cooked without salt
2 stalks celery, sliced
1 cup diced tomato
2 cups cubed, cooked chicken