In a large bowl, combine the whipped topping and pudding mix. If desired, add food coloring. Fold in the mini marshmallows and pineapple. Editor's Tip: The extra food coloring makes pistachio salad a perfect green food to celebrate St. Patrick's Day.
Cover the bowl, and refrigerate for at least two hours. This allows the pistachio salad to set for the optimal texture. Just before serving, top the large bowl or individual serving dishes with additional whipped topping if desired, and sprinkle with nuts.
