Make a FRESH PINEAPPLE MUG 

Select a fresh pineapple that is GREEN on the outside (or the cocktail may leak through the sides and bottom). A green one is also firmer and easier to handle when lifting the cocktail.
Get a pineapple corer as shown in the video (the one that turns by hand). Measure 1½ inches up from the bottom of the pineapple to where the top is cut off. Mark the corer with a permanent marking pen for that distance so that the coring does not go too deep toward the bottom of the pineapple (or it may leak).
Remove the corer and pineapple rings for later juicing or garnish. Cut and discard the remaining center core with knife.
Fill the cored pineapple with cracked ice chunks, your cocktail and a straw.