Helas
(Santa Justa - c/Gonzalo Bilbao 26 - across from Santa Justa Train Station)
Very authentic greek cuisine by a greek chef and owner. You can also buy food products and more imported from Greece. Moussaka and souvlaki are the real deal in Helas, although the restaurant is much more than that! Original recipes plus Greek wine and beer. Reasonably priced.

Acropolis
(Triana - c/Rosario Vega)
We tracked this place down after watching My Big, Fat Greek Wedding. We were not disappointed! Like Helas the owner is Greek, a very nice fellow, and also waited on us. He made some great recommendations. The plates are small but priced accordingly. While much of what we ate now escapes me I know we had a lamb stew and three other plates which were all very good. It has a nice atmosphere - about 10 tables and some seating at the bar. Of course the Greek flag and a few other bits of memorabilia were hung behind the bar.

Athenas Taberna Griega
(Triana - c/Pureza, 12)
Just across the Triana bridge and down the next street parallel c/Betis, is this tavern offering traditional Greek food in dishes as well as tapas, which makes it easy to try many of their specialties without losing too much money.