I had a single Shack Burger and the BF had the Shack Stack. Let's talk about the Shack Burger first. It comes with American Cheese, lettuce, tomatoes, and topped with Shack Sauce. To be honest, I didn't really taste the Shack Sauce that much, and also don't know what is so special about the sauce. The patty was good, the lettuce and tomatoes was also fresh, and the best thing I like about it is the hinged bun which helps hold the burger together so it didn't get messy at all. The hinged bun is probably the only advantage I see Shack Shake over Five Guys, otherwise I would rather save myself $1 and get the little cheeseburger from Five Guys with unlimited free toppings which I think taste comparable to the Shack Burger. I am speaking from memory since the last time I had a Five Guys burger was probably over a year ago, so maybe it's only fair if I do a side by side comparison. But I did eat a lot of Five Guys burger in my life since there is one right under my office.
While the Shack Burger didn't make a deep impression, the Shack Stack Burger made quite a noise. The Shack Stack is a cheeseburger with a fried Portobello Mushroom filled with melted cheese topped with lettuce, tomato, and Shack Sauce. The fried Portobello with melted cheese is fantastic, I would say that it's the highlight of the burger, and it definitely bumped it up to the star level. You can also get the Shroom burger which is your vegetarian option with the Portobello Mushroom as your burger patty. This is also a cheaper option to the Shack Stack which cost almost $9. It is kind of pricey but if I were to go to Shake Shack, I would definitely order this with no hesitation.
We also ordered the fries and a chocolate malt shake. The fries were excellent. It was not greasy at all, but I still like Five Guys greasy Cajun Fries a little more. On the other hand, even though it is called "Shake" Shack, the shakes were a little disappointing, I could not taste the malt at all. Johnny Rocket and Potbelly's malted shakes are way better than Shake Shack's. Next time, instead of getting the shake, I will get the ShakeMeister, which is brewed by Brooklyn Brewery exclusively for Shake Shack.
BTW-feel free to comment if you think Shake Shack is better than Five Guys or vice versa, I want to know what everyone thinks.