Flats Burgers is serving some of SF’s most unique smashburgers. The Excelsior pop-up’s lineup is Asian inspired—it’s the only place in the city where you’ll find a flattened longanisa patty topped with banana aioli, and a Korean-influenced version with kimchi and beef smothered in sweet kalbi sauce. It’s all sandwiched inside of a shiny, plump bun that looks like it was freshly polished, and soaks up the meat juices like a sponge. Tater tots and fries round the order out—and be sure to get some extra kimchi aioli for dipping. Flats can be found at Rocks Den daily from 5-9pm.