Place an unopened can of coconut milk in the refrigerator for at least 12 hours. You can leave it for longer, but the coconut milk needs at least 12 hours to chill and separate.
When the coconut milk is chilled, place glass or metal bowl in the refrigerator while you prep the rest of the ingredients.
While your bowl is chilling, begin layering clear glass or cups with 1/2 cup drained pineapple followed by 1/2 cup of the drained Mandarins.
Remove chilled bowl and coconut milk from the refrigerator. Carefully, without tipping the can, open the coconut milk. Gently scoop out the top layer of cream from the can and into the chilled bowl, leaving the coconut water in the bottom. (Reserve water for use in a later recipe.)
With a handheld mixer, begin whipping the coconut cream for 1 minute on medium speed. Stop and add in the vanilla and sweetener. Continue to whip until soft peaks form, approximately 2 minutes.
Once the coconut cream has been whipped to soft peaks, top each glass with cream, approximately 1/3 cup each.
You can serve immediately or refrigerate for later. Enjoy!