In a large mixing bowl, whisk together the instant vanilla pudding mix and cold milk until smooth and thickened. Let it sit for 2-3 minutes to set.
Stir in the drained crushed pineapple and shredded coconut until well combined. Add the reserved pineapple juice to enhance the flavor.
Gently fold in the whipped topping until the mixture is light and fluffy. Be careful not to overmix.
Fold in the chopped macadamia nuts (or your preferred nuts) for a satisfying crunch.
Transfer the mixture to a serving dish or individual dessert cups. Cover and refrigerate for at least 1 hour to allow the flavors to meld and the dessert to set.
Before serving, sprinkle with toasted coconut flakes, top with maraschino cherries, or add fresh pineapple chunks for an extra tropical touch.
Serve and Enjoy
