The Great Steak and Potato Factory is a western franchise restaurant that specializes in steak sandwiches, philly cheesesteaks, and burgers. There is a location in Apgujeong.
If you are looking towards the street from the Starbucks next to California Fitness, if you look across the street to the left of Bondi, you'll see a side street that runs parallel in the same direction as the Rodeo Street on that side of Apgujeong. If you walk down this street, you'll see the restaurant and a small patio on the left. As their website is under construction, you can also look at the Korean map for the Spongehouse, which is right next to it.