Back in 2010, though, a Shamrock Shake was created that was so big that it'd give Godzilla a run for its money. To celebrate St. Patrick's Day in Chicago, McDonald's created the "World's Largest ...

The Shamrock Shake is returning to participating locations nationwide starting Monday, Feb. 10, for a limited time, according to the fast food giant. This year, 25 cents from every Shamrock Shake ...