Cheese curds! Beer! (And some very cheap beer that changes every month!)
What more could you ask for? Great burgers? Okay, they have that too. Really affordable food if you stick to the burgers and various sandwiches on the menu or visit on days they have specials like fish fry night and two-for-one burgers.
HOWEVER, the tacos they serve on Tuesdays are NOT tacos. They just put whatever protein you choose on a tortilla and take it to your table. I lived in Austin, TX for two years and the tacos at The Old Fashioned just made me sad. Sorry, WI, but you don't know tacos! Stick to what you know :)