I was with CowsNeedSteroids when I ate this burger and his review pretty much sums up everything. It is easily in the top three best burgers that I have ever had. Granted, we had just finished WhiskyFest SF so it is possible that my barometer might have been off a little bit but I doubt it. The meat, the onions, the bun.. all perfect.
Also, I agree with his statement that Sarah was the best waiter that I have ever been served by. Amazing service.