White rum, coconut liqueur and pineapple blended with cream and condensed milk, served inside the frozen pineapple shell. The shell is the glass, which is why the recipe calls for whole pineapples. Makes two.
The frozen shell is the point of this version: it keeps the drink cold without more ice diluting it, and it takes thirty minutes in the freezer while you do everything else. Condensed milk is doing the work that sugar syrup does in a bar piña colada, which makes this one sweeter and heavier than the standard. If you want it closer to the original, use cream of coconut instead of the liqueur and cream, and drop the condensed milk. Blending the ice first, before the alcohol goes in, gives a smoother texture: alcohol lowers the freezing point and stops the ice breaking down properly.