The best place to get a burger in Madison, hands down. The DSG burger with caramelized onions, thick Nueske's bacon, and cooked rare to medium rare is just fantastic!
And if you're not feeling in the mood for a burger - over lunch they have a great soup and salad bar! It is one of the best I've seen with high quality ingredients, and homemade soups. Not to mention, their deserts are phenomonal most of the time!