Potato vodka is the secret of a good Vesper Martini - James Bond's own concoction. Chopin is four times distilled from Polish potatoes and named for Frederic Chopin.
Not for Vesper
Potato Vodka is not what makes a good Vesper Martini:
Fleming continues with Bond telling the barman, after taking a long sip, "Excellent ... but if you can get a vodka made with grain instead of potatoes, you will find it still better,"
25th October 2013