Blending: In the blender vase, combine pineapple, and sugar. Blend until it's liquefied. Sieve to get rid of undissolved solids. If you are making it to serve later, do this step,
Crushing ice: Add lime juice, ice cubes, and rum (if you choose to use it).Blend to crush ice to your preferred consistency. It can be made into smaller ice chunks or slushy.
Serving: Serve immediately.If you want to make it before guests arrive, follow the first step, and chill covered for later. Complete steps two and three when it's time to serve it.
Video
Notes
Fresh pineapple is preferable, but if you don't have any, use unsweetened pineapple juice, or adjust the amount of sugar to your preference.Adjust the amount of rum / vodka to your taste.