Vesper bar is casually situated on the lobby floor of the Cosmopolitan. Don't let the fact that it is at this accessible location mislead you to think it is not a serious cocktail joint. The menu has two pages. The first page contains classic cocktail while the second page has the spiced up/customized versions of the cocktails on the fist page. I tried the paradigm shift which came with a separate eye dropper of a bitter liquor that I could add as much as I would like to balance the sweetness. Highly recommended.