01 - In a large mixing bowl, combine the instant pistachio pudding mix and undrained crushed pineapple. Stir thoroughly until the pudding mix is completely dissolved and the mixture begins to thicken.
02 - Gently fold in the mini marshmallows and chopped nuts if using. Distribute evenly throughout the pudding mixture.
03 - Carefully fold in the thawed whipped topping until fully combined. Use a light hand to maintain the airy, fluffy texture of the salad.
04 - Cover the bowl with plastic wrap or a lid and refrigerate for at least 1 hour. This allows the flavors to meld and the marshmallows to soften slightly.
05 - Just before serving, top with additional whipped topping, maraschino cherries, and extra chopped nuts as desired. Serve chilled.