We also stumbled upon this place whilst walking over to see the 'magic fountain' show. We'd thought of stopping at a few places on Av. Paral-lel but it was too much of a main road. Casa de Tapas was worth walking on too. We got there about 7 in the evening and the kitchen didn't open until 7:30, but we spent the time with a nice beer and reading their amusing menu in english. All the tapas courses we had were very very good, if not a little expensive. The place got fairly full with no degradation in service. Well worth finding.