In a medium bowl, combine soy sauce, sugar, mirin, grated onion, pear, garlic, sesame oil and black pepper. Whisk to combine. Place the ribs in a large resealable ziploc bag then add the sauce mixture. Gently coat the ribs with the sauce. Marinate in the fridge overnight for best result but 4 to 5 hours should be ok too.
Preheat gas grill to medium high heat. Grill the short ribs for about 3 to 4 minutes per side.
Caramelized onions with olive oil and butter for about 10 minutes over medium heat then season with salt and pepper. Serve ribs with caramelized onions and green onions. Yum!
Recipe by Gluten-Free by Jan at https://glutenfreebyjan.com/gluten-free-kalbi-korean-bbq-beef-short-ribs/