For anyone reading this, I really can't believe all of the answers missed out on one of the best places to get a coffee in Barcelona; Café el Magnífico!
There are loads of other places too like Satan's Coffee Corner, and Mesón del Café. You can read about them in more detail here: http://www.things-to-do-barcelona.com...
El Celler de Can Roca is another 3 star michelin restaurant in the Catalonia restuarant but is much further from the city can Sant Pau, but also worth a visit if you can.
You can find a list of all Michelin star restaurants in Barcelona here: