It's soon to be Shamrock Shake season. McDonald's Shamrock Shake, a milkshake made with vanilla soft-serve ice cream, artificially-flavored minty green syrup and whipped topping, will return to restaurants on Monday,

McDonald’s is bringing back its beloved Shamrock Shake with the help of an old friend. The minty green milkshake will return to restaurants on Monday, Feb. 10 — and the chain’s Uncle O’Grimacey character is returning after a decades-long hiatus to help kick off the annual “Shamrock Season.”