Just as fall marks the return of the pumpkin spice latte and winter the arrival of peppermint hot cocoa, every spring can be counted on to mark the homecoming of the Shamrock Shake–a creamy, green milkshake that has fascinated consumers ever since it hit select menus in 1970.
St. Patrick’s Day may be the third most popular drinking day in America, but green beer isn’t the only thing on the menu. An invention the famous global burger chain McDonald’s, the Shamrock Shake has become a coveted St. Patrick’s Day tradition. Ahead of the coming holiday, we’re exploring the origins and persisting success of this sweet treat.