My wife and I came across this restaurant by accident while staying on the Ile St Louis. We ended up going there several times during our week stay in Paris because we enjoyed it so much.
Le Tastevin is a small but ‘cozy’ restaurant (I think there were only around 10 tables) with a very ‘french’ atmosphere.
I wouldn’t say it’s cheap (although we don’t find many cheap places to eat in Paris these days!). We tried the tasting menu for 67 euros. You can eat things like foie gras and snails (escargots). If you’d prefer something a little more conservative though, there was steak on the menu!
We highly recommend this place – a friendly, unpretentious restaurant in the heart of Paris.