1. Preheat broiler. Place chicken in small broiler pan and broil 4 inches from heat until lightly browned, about 3 minutes. Turn and broil until other side is lightly browned and chicken is cooked through, about 2 minutes longer; set aside to cool. Cut into 1/2-inch diagonal strips.
2. To prepare sauce, in small bowl, whisk together remaining ingredients, except tomatoes and snow peas, and 1 teaspoon water. Pour into small serving dish.