If you find yourself in Cambridge, and you're craving guacamole (and honestly, who isn't?), get yourself over to Ole Mexican Grill in Inman Square. I went there for dinner last night, and man, that guacamole. It was, hands down, the best guacamole I've ever had. EVER. They prepare it table side (although from where I was sitting it was more like, behind me and out of my peripheral vision) so I didn't see the magic happen, but I'll definitely pay more attention next time. They make it in a molcajete, one of those big, rough looking mortar and pestle things. The avocados were perfectly ripe, and there was plenty of lime, cilantro, salt, and either red onion or scallion to make it absolutely delicious. Essentially, it was exactly the way I like it. One bowl is enough for 4-6 people (although I could have probably eaten it on my own...)
An interesting tidbit I learned from Leo Romero, chef/owner of Casa Romero in Boston: The Mexican government recognizes only 46 Mexican restaurants in the US and Canada as "authentic." Apparently, Casa Romero and Ole are both on this prestigious list, which is why both have been on my "Restaurants to Try" list (yes, I have one of those). While my Google searches to confirm the existence of such a list have come up empty, Leo seemed like a trustworthy guy. And in any case, authentic or not, the guacamole makes Ole a restaurant worth visiting.