Add ice, pineapple juice, rum, if desired, and cream of coconut to bowl of blender. Blend on high speed until ice is crushed, ingredients are combined and drink is smooth, about 30 seconds.
Pour into glasses. Serve with pineapple wedge and cherry, if desired.
Measuring ice for our Piña Colada recipe can be tricky; You place the frozen cubes in your measuring cup, because of the gaps between the ice, you can’t be sure that 2 cup read is accurate. For a no-fail method, first, add 1 cup cold water to a liquid measuring cup. Then add the ice cubes one at a time. Once the waterline reaches 2 cups, you’ll know there’s exactly 1 cup of ice; drain the water and add the ice to the blender.