I just went, and I recommend you do the same...
You'll need to make a reservation (93.329.22.38) because there are only seats for approx 18 people. The restaurant is run by an Australian-transplant, Sarah, ably assisted by two or three others, including a fabulous pastry chef. The decor is simple, as the focus is clearly on the food. The kitchen is partially open, so you can keep an eye on Sarah busily plating each dish.
Only the wine list is printed; the dinner list changes daily, depending on the season and Sarah's mood. We selected a very good Rioja after getting some advice from the only other front room staff. The meal began with a fabulous homemade bread, accompanied by an excellent olive oil and a sesame-cumin-almond-&c ground mixture for dipping.
Shortly after we arrived, Sarah joined us at our table to explain the menu options for the evening. There was a 3-course menu (for approx 35 euros) and a 5-course menu (for approx 55 euros). The 3-course menu included a choice of 2 starters, 2 mains, and 4 or 5 desserts. The 5-course menu had no choices (other than dessert) - two starters, one main, one cheese course (3 cheeses), and dessert. One starter, just to give you an example, was asparagus topped with a poached egg and shaved cheese, with a side of a very delicate spanish ham. Other items that appeared on the menu included figs, gnocchi, quail, and even a thai-style pork dish (which Sarah explained "was what I felt like eating tonight"). The five course menu isn't really more food than the 3 course menu (which included a very large main course).
Desserts feature fruit in season - I had an apricot tart with mascarpone cheese that was amazing, although it meant passing up an equally appealing cherry-themed dish. We also tried a homemade dark chocolate ice cream sandwich, assembled between two different cookies (choc chip and espresso).
The service was excellent, and the pacing of the meal was relaxed (although I noted that some other tables - who only ordered the 3 course menu - received their food at to rushed a pace for my taste - I think the fact that we ordered one 5-course menu slowed everything down).
My only complaint was that smoking is allowed indoors (not in keeping with many Barcelona restaurants). The people next to us (sitting very close) had a cigarette between each of their courses, which corresponded to *during* each of our courses. This compromised our ability to really take in the aromas of each dish, which was a disappointment, and frankly a surprise. After all the effort Sarah takes in selecting the finest ingredients, crafting unique yet simple dishes, and assembling them into exciting menus -- well, I would think she would want to spare the food from a smoky veneer. If you are someone who can't enjoy a meal next to a cigarette, you might not want to risk eating here.