'www.youtube.com/embed/Gcakv7G4PBM' There are some places you hear about, some you stumble upon, and then there are places like Yanggun Sushi n Tuna in Jamsil – a true hidden gem that will redefine your expectations of value and quality. Tucked away quietly in the basement of an old, unassuming apartment complex near Jamsil Station, this isn't your average sushi spot. Our reviewer, a seasoned foodie, initially visited out of curiosity and left profoundly impressed, even "worried about the owner's generosity!" Discovering Jamsil's Hidden Treasure Finding Yanggun Sushi n Tuna is part of the adventure. Located a mere 9-minute walk from Jamsil…