I know I’m kind of late into the game, but yes! Finally got my hands on ShakeShack! To be exact, I had their Shack Stack ($14.30) which consists of a Cheeseburger topped with the Shroom burger served with Shacksauce. & I really enjoyed the burger against the mixed reviews. I find the Shroom patty was crisp-fried to golden brown, which was really crispy on the outside, and oozing with juiciness from the portobello and cheesiness from the Cheddar and Muenster with a bite into it! Even the meat patty itself is moist and hearty! Not too bad a first experience for me!