If his first subject -- Top Notch Beefburgers -- hasn't been written about on LTH I wanted to add a few lines because it really is a unique experience.
The meat is ground and made into paddies every day. Not frozen. Not made one day and cooked the next.
The fries are cooked in lard, not oil. And they are always perfectly done. Fries, too, are cut every day. They pre bake, let cool and then fry throughout the day.
I think Kevin made a mistake by ordering the 1/2 pound burger as the the extra 1/4 of meat alters the ratio of bread, meat and cheese. Darin once tutored me on how to make a perfect burger which was pretty much summed up in don't try too hard (like the foi gras, etc.). Defy the overwhelming temptation to press down with the spatula while its cooking.
The classic and I think the best in the city is the regular burger with grilled onions (that are cooked on the same grill as the burgers). It comes with catsup and pickles.
The lettuce and tomato are there for aesthetics. Under no circumstances should they be put on a top notch burger.
By the way, Darin, who is the longtime owner and cook, got his MBA from University of Chicago in the 50's. Which he's used to run a greasy burger joint. He's lived a happy life.