Near the end of South, Florencia Iriondo's autobiographical show, the Argentina-born writer and performer explains, "That constant sense of nostalgia defines me more than any address can." Nostalgia takes myriad forms in this musical monologue, and the sounds, stories, and even the tastes of South America emanate, intermingle, and blend together in the cozy Huron Club at SoHo Playhouse, where South has taken up tempo…
