We had been tipped off by a colleague that this place did exceptional food and not to worry about it looking a little tired on the outside. This was spot on advice. From the outside it looks like a small bar with a few tables that might do for a quick beer before heading off to a "proper" restaurant for a big steak. Nothing could be further from the truth.
When you go in the ambience quickly becomes apparent. Latin style music plays (not too loudly) and the waitress greets you in a friendly and informal manner. We were seated and pretty soon had a bottle of excellent Malbec in front of us.
If I had to find one fault I would have to say that after we ordered is was a pretty long time before the food arrived. But on the other hand the company was good, the place made us feel relaxed and welcome and, most importantly, the food was really worth the wait. I had the Lomo dada which came with a creamy mustard sauce and potato dauphinoise. It was delicious, and cooked just right. I've had plenty of good steak in Argentina, but this was a little bit different and really special. The others had a rib-eye steak which, unusually, came with a salsa style sauce on top which they also highly commended.
So I would thoroughly recommend the "Dada bistrot" (sic). But don't go if you are in a massive hurry or if you are a big group, since it works at its own pace and is only small.