In his book Milkshake Monday, author and TikTok sensation Larry Canam wrote how he was inspired to turn the classic dessert cocktail into a milkshake by John Lennon. The story goes that when Lennon first tasted a Brandy Alexander in March 1974 he "later said the drink 'tasted like milkshakes.'” And considering the original is a simple mix of brandy, creme de cacao, and heavy cream, its transition to milkshake is seamless.