Pizzeria La Città Di Pulcinella
You can find La Citta Di Pulcinella at the top end of Via di Leuca, almost as far as Castromediano but still only a 15/20 minute walk from Porta San Biagio.
It's a rock solid Neapolitan pizzeria complete with fake interior Napoli balconies (with clothes hanging from them), check table clothes, and Moretti on tap.