Korean Sweet Potato Noodles (Japchae)

In a bowl, whisk together 1/4 cup soy sauce, mirin, 1 tablespoon sesame oil, minced garlic, and 1 teaspoon black pepper. Add the sliced flank steak and ensure it's well coated. Allow to marinate for at least 30 minutes to infuse the beef with flavor. (Marinating time: 30+ minutes)

In a large bowl, prepare the noodle sauce by combining 1/4 cup soy sauce, honey, 1 tablespoon sesame oil, and a pinch of black pepper. Stir until well mixed. This sweet and savory sauce is the heart of Japchae.

Bring a large pot of water to a vigorous boil. Add the Korean sweet potato noodles (dangmyun) and cook according to package directions, usually around 5 minutes, until they become translucent and slightly chewy. Drain the noodles thoroughly and immediately transfer them to the bowl with the sauce, tossing to coat evenly. (Cooking time: ~5 minutes)

Lightly whisk the egg in a small bowl. Heat a lightly oiled skillet over medium-low heat. Pour the egg into the skillet and cook until it forms a thin omelet, about 1 minute per side. Remove from the skillet and slice into thin strips to create a delicate garnish. (Cooking time: ~2 minutes)

Bring another pot of lightly salted water to a boil. Add the baby spinach and cook until just wilted and bright green, about 1 minute. Immediately drain the spinach in a colander and plunge it into a bowl of ice water to stop the cooking process and preserve its vibrant color. Drain well, squeezing out any excess water. (Cooking time: ~3 minutes)

Heat olive oil in a large skillet or wok over medium-high heat. Add the carrot matchsticks and sliced onion, and sauté until they soften and become slightly translucent, about 5 minutes. Add the marinated steak and cook until it's browned and cooked through, about 5-8 minutes. Stir in the blanched spinach. (Cooking time: ~10 minutes)

Add the sauced noodles and egg strips to the skillet with the vegetables and beef. Toss everything together, ensuring the noodles are well combined and heated through. Cook for an additional 2 minutes, allowing the flavors to meld together. (Cooking time: ~2 minutes)