Dan Ryan's Cheeseburger: loads of cheddar, good crispy fries and macaroni salad. I know the macaroni salad seems weird, but it's good. Actually, they give you cole slaw now unless you ask for it the old way.
Poll's over, but I gotta say Bravo Burger. The only other burger I've eaten in Taiwan that has ever come close to Bravo's was the burger Andrew used to make at a food court stand in Zhonghe before he opened Bongo's. Those were wonderfully spiced.