Slice the thick white part of the green onion in half longways so the white part is not too thick. Cut the green onion into about 2 inch long strips.
Heat a medium-sized pot on medium heat, add the oil and sesame oil when warm. Toss in the beef and stir-fry in the pot. Once the beef is no longer pink, add in all of the green onion. Continue to stir-fry until the green onions lose its volume by half. (In the beginning it will look like too much green onion but as they stir-fry, they will lose their volume. )
Pour in the soup soy sauce and fish sauce. Continue to stir-fry for 1-2 minutes. Make sure the bottom of the pot doesn’t burn. Pour in the water and also add in the kelp pieces. Allow to come to a boil and continue to simmer. I like to cook it for at least 10 minutes.
Sauce: While the soup simmers, make the sauce! add all the sauce ingredients in a small bowl and mix well. Set aside for a few minutes.
Take the kelp out and set aside. *Optional, Chef Baek Jong Won slices the kelp into long strips and puts it back into the soup. I prefer to leave it out!
Add in the minced garlic, and continue to simmer. Season with salt and pepper to taste. Simmer for another 5 minutes for all the flavors to come together.
Serve with a bowl of white rice and kimchi! Try the soup on its own first. Then place a small spoonful of the sauce to the side of the soup bowl a little and take a taste of the soup! It will have a very different flavor.