How do I cook Korean Cold Noodles (Mul Naengmyeon)?
Here's a recipe for Korean Cold Noodles (Mul Naengmyeon):

Ingredients:

Broth

• 1 lb flank steak
• 2 green onions, halved crosswise
• 2 small white onions, halved lengthwise
• 1 dried seaweed
• 1 slice fresh ginger
• 1 head garlic, halved crosswise
• 1/4 cup rice wine
• 2 tablespoons korean soup soy sauce
• 1 tablespoon korean beef stock powder, or beef bouillon
• 1 tablespoon granulated sugar
• 1/2 tablespoon sea salt
• 2 teaspoons freshly ground black pepper
• 8 cups water
• 4 cups water radish kimchi brine, cold

Noodles

• 1 lb naengmyeon noodles, buckwheat and sweet potato noodles

Toppings

• pickled radish, thinly sliced
• 1 persian cucumber, julienned
• 2 hard boiled eggs, peeled and halved lengthwise
• toasted sesame seed

Instructions:

1. Make the broth: In a large pot, combine the flank steak, green onions, white onion, dried seaweed, ginger, garlic, rice wine, soup soy sauce, Korean beef stock powder, sugar, salt, pepper, and water. Bring to a boil over high heat, then reduce the heat to medium and simmer for 1 hour.
2. Remove the flank steak from the broth and let cool on a cutting board. Let the broth cool to room temperature, about 30 minutes.
3. Line a fine-mesh strainer with at least 2 layers of cheesecloth. Strain the broth into a large bowl. Refrigerate the broth until cold, about 1 hour.
4. Once the flank steak is no longer hot to the touch, cut into 1/2-cm-thick slices.
5. Stir the water radish kimchi brine into the cold broth.
6. Bring a large pot of water to a boil. Add the naengmyeon noodles and cook according to the package instructions. Drain the noodles and run until cool water until cold.
7. Divide the noodles between 4 serving bowls and ladle about 2 cups of broth into each bowl around the noodles. Top each bowl with 4–5 slices of beef, pickled radish, cucumber, half of a hard-boiled egg, and sesame seeds.

Enjoy your Korean Cold Noodles (Mul Naengmyeon)!