I've pretty much tried all of the food at AT&T Park. For the past two games, I've been bringing food. The benefit is that it's a bit cheaper and I don't have to stand up as often during the game to get food.
Java House, San Francisco
This is along the Embarcadero right by the ball park. Don't mistake this with Red's Java House farther down the road. That's the place that Anthony Bourdain visited in his most recent SF episode.
On a french roll. This patty was smothered in chili, cheese, onions, and jalapenos. Pretty decent.