The fried chicken sandwich is shockingly simple but perfect. No wonder more and more are popping up across Miami and America. In mid-January, Shake Shack began serving its version, aptly named the Chick'n Shack, across the nation. Restaurateur John Kunkel's 50 Eggs Inc.'s fast-casual concept place Spring Chicken opened the same month with a fried chicken thigh sandwich called the Yardbird. It serves another with the bird fried or grilled and dressed with Swiss cheese, pepper bacon, pickles, and buttermilk ranch.

But skip the big boys. Miami's best version can be found at Jeremiah Bullfrog's GastroPod (160 NW 26th St., Miami; 786-228-6704; gastropodmiami.com). The "chicken sammich" ($8) is a secret homage to the Chick-fil-A classic that has drawn a cult following. It joined GastroPod's menu — beloved for its tangy purple slaw, short-rib sliders, and a crisp arepa adorned with goat cheese and spicy mayo — about two years ago.

The original incarnation offered chicken thighs brined in buttermilk and fermented Korean chili paste called gochujang. That preparation was nixed in favor of a simple buttermilk-and-salt brine that pumps moisture into every fiber as the meat marinates. "The chicken keeps getting better and better," Bullfrog says.

After it's pulled from the marinade, the thigh is coated in a blend of flour and either corn or potato starch. The combination creates a distinctive crackly crust. It's fried and topped with two paper-thin house-made pickles and then cradled in a spongy Martin's potato roll. A squiggle of spicy mayo is optional, but don't miss it — it imparts the same heat the gochujang provided in the original and is what helps set this bird apart.

Such a creation could surely hold its own against John Kunkel's and Danny Meyer's versions. "When we do Bonnaroo, we sell 500 in a day, 2,000 over the festival," Bullfrog says. But a dedicated fried-chicken-sandwich place isn't on the horizon. Instead, the sammich will keep pecking around GastroPod's classic menu.

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