Combine the first 4 ingredients in a saucepan; bring to a simmer. Cover and simmer for 15 minutes or until the chicken is done. Remove the chicken pieces from broth; cool and coarsely chop. Bring broth to a boil over high heat; cook until reduced to 1/4 cup (about 5 minutes). Cool.
Spoon yogurt onto several layers of heavy-duty paper towels, and spread to 1/2-inch thickness. Cover with additional paper towels, and let stand 5 minutes. Scrape into a bowl using a rubber spatula.
Combine the reduced broth, yogurt, mayonnaise, and next 7 ingredients (mayonnaise through black pepper) in a large bowl. Stir in the chicken, pasta, and the remaining ingredients. Cover and chill thoroughly.