We stumbled upon this place while walking around Amsterdam and ended up eating here twice in our stay. The staff are friendly and helpful, they also have an english menu and free wifi. The first time we had the Boca's sample plate (small) which had some blue cheese, smoked salmon, steak, and fish with bread, as well as steak tartare and a mini lamb burger. Everything was excellent and came to only 32 euros including drinks. The food is generally 'small bites' so you can order lots of different things. This is why we returned and had the duck confit, bruchetta with steak and foie gras, and bitterballen and different kinds of chips and mayo.
We ate early both times, and when we arrived we could see that many of the tables are reserved, so if you prefer to eat later, it may be helpful to make a reservation.
Also they only take cash or debit, no credit cards.