De Groene Vlinder (Green Butterfly) can be found on a crossing street on the Albert Cuypstraat. And that, you will notice in their service. Very Dutch and direct. There is a chance the waiter shouts your order to his companion in the kitchen, just like a salesman at the market would. Don't be shocked, they put a hint of humor in it.
If you want to experience the typical café food Amsterdam bars offer, this is your place. Always a daily special and overall very affordable. In weekends this place is also a very popular place for locals to hang out, have a beer and show some dance moves.
Don't expect too much from the food, since there are many different cooks because most of the staff are students. But ey, that is the charm of it.
Mon-Su: 10:00-01:00
Fr-Sa: 10:00-03:00