Start by letting the bag of frozen pineapple thaw on the counter for 20 minutes. This will help the pineapple chunks break down easier, without adding too much liquid. You can measure the other ingredients and add them to the blender while you wait.

Add the pineapple to the blender with the other ingredients, secure the lid, and blend until the mixture looks thick and creamy. Use a tamper to help the ingredients break down, if available. Otherwise, stop and scrape down the sides several times, until the mixture looks smooth.

You can serve the pineapple whip right away by scooping it out of the blender into a dish. For a soft-serve presentation, transfer it to a gallon-sized zipper bag, flatten it as much as possible, and seal it. Place it in the freezer for 30 minutes to firm up for the best texture. (That way it won't melt too fast.)

Once it's firm, knead the bag to make sure it's thick and slushy. Then, cut off one corner of the bag to create a piping bag. Pipe the pineapple whip into serving dishes and serve right away. If you have leftovers in the bag, seal the corner you cut off with a clip and freeze for up to 3 months.