Bodega Sepúlveda is a classic old-fashioned Barcelona bodega — wine in carafes from the barrel, pintxos on the counter, marble tables worn smooth by decades of elbows. The kind of place that has been serving the Eixample neighbourhood since Franco was in power and shows no signs of changing.
Order whatever is on the counter. Drink the house wine, which is cheap and perfectly fine. Eat standing up if the tables are full. This is the anti-tourist Barcelona that increasingly hard to find, and it is entirely genuine.