"This pop-up is serving some of SF’s most unique smashburgers. The Flats lineup is Asian inspired— it’s the only place in the city where you’ll find a flattened longanisa patty topped with banana aioli, or a Korean-inspired 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. Flats can be found at Rocks Den daily from 5-9pm." - julia chen 1, patrick wong, lani conway