Authentic places - South Beach Miami
In no particular order
Jugofresh (not my usual thing but the sunset harbour bowl and sana de rana are both very good, sunset harbour being the best one)
Joe's Takeaway (opens the 15th)
Otentic -- not very local (french) but good. They may have moved to south of 5th by now, you will need to check if you are interested in going. Have not been in a while.