Boil chicken breast until done. Set aside to cool.
While chicken is cooking drain pineapple. Reserve the liquid. Peel apple and cut into small chunks. Place apple chunks into reserved pineapple liquid (this will prevent apple from browning). Cut grapes into halves.
When chicken is cool, cut into bite size pieces, and place in bowl. Drain apples and add to chicken, add grapes and pineapple. Add mayo and Cool Whip. Chill. Top with walnuts or almonds and serve.