When in Tampa, I love to stop in at Fruti Cuba Coppelia on Kelly Road, for an authentic batido made from Mamey. They have plenty of other goodies, too, but since I'm a confirmed Mamey junkie, I never try anything else.
The fruit of the Mamey tree, aka Zapote, aka pouteria sapota, is popular in Mexico, Central America, the Caribbean, and Florida. But for some reason, this open-secret ingredient is hard to come by everywhere else. Mamey is usually eaten raw and is often made into milkshakes, smoothies, and ice cream. (It's also widely considered in the Latin-American world to be an aphrodisiac.)