Manduguk

1. Stage

Trim chuck roast and cut into 1 1/2-inch thick by 1 1/2-inch wide strips. Quarter onion, leaving roots intact.

2. Stage

Place beef and onion in a large pot with light scallion parts, garlic, ginger, and peppercorns. Add water and bring to a boil over high heat, skimming off any foam that rises to the surface. Reduce heat to low and cover with a lid, leaving it slightly askew. Cook, adjusting the heat as needed to maintain a gentle boil, until beef is tender and easily pierced with a knife, about 1 hour 30 minutes. Turn off heat.

3. Stage

Transfer beef to a heat-proof bowl and spoon some of the cooking liquid over top to moisten. Let rest until cool enough to handle, about 20 minutes, then shred into bite-sized pieces.

4. Stage

While the beef is cooling, strain broth over an 8-cup heat-proof measure. Discard solids and return broth to the pot. Stir in fish sauce, salt, and pepper.

5. Stage

Separate 1 egg into 2 small bowls; stir egg yolk until runny.

6. Stage

Heat 1 teaspoon canola oil in a small nonstick skillet over medium-low heat. Rub oil with a paper towel to coat sides and bottom of the skillet with a thin layer. Scrape egg yolk into the skillet with a rubber spatula. Remove from the heat and swirl to evenly coat the bottom of the skillet. Return to the heat and cook, undisturbed, until egg yolk is pale-yellow and the surface looks dry, about 1 minute. Turn off heat and gently flip with a spatula. Let sit for 1 minute, then transfer to a cutting board. Cut egg yolk sheet in half, then slice crosswise into thin strips. Wipe the skillet clean.

7. Stage

Prep and heat the skillet in the same manner with the remaining 1 teaspoon canola oil and a paper towel. Cook egg white until it turns opaque and bubbles form on the surface, about 45 seconds. Turn off heat and let sit until set, 1 to 2 minutes. Gently transfer to a cutting board and slice as you did for the egg yolk sheet. Set aside.

8. Stage

Return broth to a boil over high heat. Add dumplings and cook until they float and reach an internal temperature of 165 degrees F (74 degrees C), 5 to 7 minutes. Reduce heat to a gentle simmer over medium.

9. Stage

Slowly drizzle beaten eggs into the simmering soup. Cook until eggs set, about 5 seconds. Remove soup from heat and stir in reserved dark green scallion parts, sesame oil, and additional salt to taste.

10. Stage

Ladle soup into bowls and top with egg white and egg yolk strips. Garnish with nori.