There's one Indian restaurant close to, or just off, Calle Florida. Don't remember the name. It's pricey by local standards. The owners aren't Indian. But they do use real spices (and use this as a plausible pretext for their prices). Other then that, I can't think offhand of a single authentic Indian restaurant. As far as I know, the only thing "Indian" about the restaurants purporting to be so is their names (e.g. the Bangalore). Neither the owners nor the chefs are Indian. Hence neither is the cuisine.