Casa Pachuco was recommended to us by a real foodie, so we decided to seek it out in the Lavapiés district. The place is small, there are only some 8 tables, so I would recommend a reservation, as also locals prefer this place. As in most places in Madrid, it is so and so with English, but there is a menu in English and the younger waiter handles it OK. I would recommend eating "compartir" i.e. sharing each of the tapas whomever you are eating out with. The tuna with wasabi+avokados is a must. Also the squid was great. For vegans and all else too, we recommend the Brussel sprouts.