Cook chicken breasts in salted water for 20 minutes, or until done. Remove chicken to a bowl filled with ice and water. Let chicken stand until completely cold. Pat dry.

Dice chicken; place in food processor bowl fitted with blade. Mix mayonnaise, milk, lemon juice, salt, pepper, dry mustard, pickle relish, and egg yolk. Po ur about half on chicken. Pulse process until well mixed. Add more of the mayonnaise mixture and pulse, until the proper consistency has been reached. Add chopped egg white and celery. Pulse process until well blended. Remove chicken mixture to a bowl. Add sliced grapes and stir to blend. Garnish with parsley. Serve on a bed of shredded lettuce. Yield: 4 servings.