The first time I was in Mexico City, I wasn't in love with the food I found in restaurants. To be fair, I had just come from Oaxaca where I don't think I put anything less than stellar in my mouth. The best thing I ate in Mexico City was some kind of fried masa treat with cheese and chiles that I had right on the street outside of a Metro station. I still dream about it. But there were lots of uninspired meals and I realize now it was mostly because I didn't know where to go.
I wish I'd had a copy of Nicholas Gilman's Good Food in Mexico City back then. I've know Nick from the online food boards for years so when I knew I was going to be in Mexico City this last January, I made it point to meet him in person.

Nick took me to El Tizoncito, which is one of the many places written up in his book. The afternoon went by in flash but I do remember some outstanding salsas and charro beans.
What I like best about Nick's book is that it's opinionated and yet very straight forward. I used it for the entire trip and it didn't once let me down. I've shown it to friends who know Mexico City well and they can't wait to pick it apart and show me places he's missed but then they find he's covered them. I have to assume my friends feel very protective and territorial about Mexico City, or I have some nasty friends. Either way, Good Food in Mexico City passes with flying colors.