Prep Time: 10
Cook Time: 10
Serves: Serves: 2
Place chicken between sheets of plastic wrap or wax paper and pound with a meat mallet to 1/3-inch thickness.
Combine mustard, mayonnaise, tarragon and garlic. Place chicken on rack of broiler pan. Spread half of mustard mixture over chicken. Broil 4 to 5 inches from heat 5 minutes. Turn; brush remaining mustard mixture over chicken. Continue to broil 3 minutes. Place cheese over chicken and continue to broil until chicken is no longer pink in center and cheese is melted, about 1 minute. Place chicken and tomatoes on toast.