We tried McDonald's classic Shamrock Shake next to its biggest competition ever — here's the verdict -

Hollis Johnson

McDonald's much-loved seasonal Shamrock Shake now has competition in the form of Burger King's new Oreo Irish Mint Shake. 

The Shamrock Shake has amassed a cult following since its inception in 1970; the sight of the minty green shake is a sure harbinger of spring and vaguely Irish themed kitsch. 

But with Burger King's release of the Oreo Irish Mint Shake, McDonald's reign over the green-dyed seasonal milkshake market is being threatened.  

Now the Shamrock Shake is available, and a taste comparison is in order. Is Burger King's launch a vain attempt to disrupt the mint milkshake market, or will the addition of Oreo crumbles dethrone the iconic Shamrock Shake?

Burger King's latest shot in the fast food wars is the Oreo Irish Mint Shake, a limited release that's pretty clearly aimed at McDonald's classic Shamrock Shake.

Hollis Johnson

BK's shake is on the left; notice the Oreo crumbles dotting the slightly gray shake. McDonald's is much greener — gotta love that food coloring.

Hollis Johnson

First, let's re-familiarize ourselves with the one, the true: the Shamrock Shake. It comes in small, medium, and large; the medium, seen here, cost $3.89. That's absurd NYC pricing, so it's likely less just about anywhere else.

Hollis Johnson

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