(For the non-alcoholic, dry ice-free version, see the color-changing sports drink)
Step 1: Ingredients
Gin (or vodka, for a vodka martini) ~ Vermouth ~ Dry Ice ~ Baking Soda ~ Red Cabbage
Step 2: Red #$@%! Cabbage?
To get the indicator, chop up a cabbage leaf, put it in a bowl with some water, and microwave until it's boiling (or just add boiling water and allow to steep). A purple pigment will stain the water.
Step 3: Build
Step 4: Present
(that's not me saying "wow, that's wicked" by the way. This drink was mostly made as a way of keeping three small children entertained while their mother was out Christmas shopping. They liked the look of the cocktail, but thought the mocktail version was "really disgusting". I did warn them that it was just salty, cabbage-flavoured water...)It should go without saying, but wait for the dry ice to disappear before trying to drink the cocktail. You do NOT want to swallow any dry ice!