I tried every custard shake at Shake Shack. Here's how they rank from worst to best.

A writer has tasted and ranked 17 of Shake Shack's shakes over the past year, including the newly released Biscoff Cookie Butter Tiramisu shake. The ranking includes classics such as chocolate and vanilla, as well as limited-edition flavors like the Dubai Chocolate Pistachio. The Biscoff Cookie Butter Tiramisu shake earned the No. 2 spot in the ranking, behind a classic. Shake Shack did not respond to a request for comment.

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