I hadn't been there for 11 years but the cheeseburger at Cassidy's was just as good as I remember it when I went there for lunch today. That Pepper Plant sauce really gives it a unique flavor, and the burger is already great.
It's a pretty standard burger: probably half pound of what tastes like ground chuck or some fatty ground beef and I think it had lettuce, tomato, red onion and pickles on it. It may have had mustard between the patty and the bottom bun, but I'm not sure. I ate it too fast to stop and look. Add a healthy dose of the pepper plant sauce and it's really tasty.
I will be back many times in the next 11 years.