Preheat oven according to instructions on box. Prepare box mix adding the ingredients listed above.
Fold in carrots, walnuts, and pineapple if you add those. Fill half way with batter.
Bake for 15-20 min. or until cooked through and springs back. Cool. Frost. Use an electric mixer to whip the cream cheese and butter together and then add other ingredients creaming them together until combined.
Fill pint sized freezer baggie, cut corner off and squeeze on cupcakes.