U-boot (cocktail) named after submarine
A U-boot is a beer cocktail that is made by placing a shot of vodka into a glass of beer, typically a lager.  It is popular in Germany, Poland, North Macedonia, and Flanders. In Germany, the liquor korn is sometimes used instead, while in Flanders and the Netherlands, jonge jenever is preferred.
It is called a U-boot (German abbreviation of Unterseeboot, "submarine") because the shot glass of vodka sinks to the bottom of the glass of beer. The shot glass then "surfaces" when the cocktail is drunk.
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