I was incredibly happy to happen upon this place. It's right next to a lovely, unique green space: Parque Berros. Note that the restaurant may be very difficult to spot, as it has no sign and no clear number. It's the orange wall with a door next to a green building, right on the side of the park.
Excellent set meal options, great soups, some of the tastiest salsa I've had in ages. Very nice outdoor seating area with hummingbirds and butterflies... also plenty of seating indoors. Gets packed with locals during lunch hours. Highly recommended!
Cons: hard to find, closed evenings