Vodka, coffee liqueur, and heavy cream over ice — 'The Dude abides.' The Big Lebowski made this perfect.
The White Russian was created in 1949 — the same origin as the Black Russian (Hotel Metropole, Brussels) — by adding cream to the existing two-ingredient drink. It was popular in the 1970s then largely forgotten until the 1998 Coen Brothers film 'The Big Lebowski', in which The Dude (Jeff Bridges) drinks approximately nine White Russians over the course of the film.
'The Big Lebowski' gave the White Russian a cult following that it retains today. 'Lebowski Fests' celebrate the film annually, and White Russians are consumed in enormous quantities. The drink works because Kahlúa's coffee-rum sweetness, heavy cream's richness, and vodka's clean spirit create a genuinely pleasant, easy-drinking combination — dessert in a glass.
Omit the cream. The two-ingredient parent cocktail.
Use whole milk instead of heavy cream. Lighter, lower in fat, and what The Dude might drink if he was watching his figure.
Replace cream with coconut cream and use coconut rum instead of vodka. A tropical, dessert-style variation.