I read many of these message boards before my trip to Spain. Lots of great food was consumed thanks to all of your info. Here are a few highlights.
Tapas at El Tempranillo - tried the huevos relletos with rioja. Very good and great price. Lots of locals everywhere.
Tapas and wine tour with Andres Jarabo - he brought his own wine and took us and a few other couples around to his favorite places. Sampled PX or Pedro Jimenez with vanilla ice cream for the first time (and certainly not the last). Vermut de grifo (vermouth on tap). Also, best paella at the last restaurant he took us to. It was not cheap but worth it.
Casa Mingo - not sure if I read about this here but a coworker from Madrid recommended it. Off the beaten path, no tourists. Amazing. Waited in line for 45 mins and then ordered what everyone was eating - rotisserie chicken and cider. So good. Very cheap.
Abantal - Go. Our BEST MEAL IN SPAIN! Amazing. Expensive but not ridiculous. We got the tasting menu with wine pairing. The culinary highlight of the year. The location is strange and the atmosphere is definitely not romantic but wow. Wow. I've attached some photos from that meal.
Nothing really stands out here. The food was good but not incredible.
Gellonch - I know there is a lot of love for this newcomer on these boards but I thought it was just okay. THe service was very good but eh. We paid a lot and only one dish was memorable. I would skip it and save your cash.
Restaurant St. Joan - lived up to the hype. Very good. There was a language barrier but we were able to procure some amazing steak, pollo croquettes and pork. Paid just a few euro for some of the best food we ate in BCN.
Cafe l'Academia - touristy but very good. Great vibe. Loved the food and while the prices were high they could have been much higher. One of our favorites.
4gats - The food was pretty decent but huge portions and very expensive. I started off sour because the waiter tried to upsell me to a bottle of wine 3 times the price of the one I'd chosen. The dessert was not good at all.
Tapac24 - very good, trendy, young tapas in the Eixample. We didn't have reservations but they found us a seat. We had the McFoie burgers which did not disappoint.
Thanks for all your help!