Japchae Sweet Potato Glass Noodles

Thinly slice the beef and marinate it with 1 tbsp soy sauce, 1 tsp sugar, 1 tsp sesame oil, and 1 minced garlic clove. Set aside to marinate for at least 15 minutes while you prepare other ingredients.

Boil a large pot of water. Cook the sweet potato glass noodles according to package directions (usually 6-8 minutes) until tender and translucent. Drain well, rinse with cold water to prevent sticking, then cut into shorter strands with kitchen shears. Toss with 1 tbsp sesame oil to prevent sticking. Separately, blanch the spinach in boiling water for 30 seconds, then immediately transfer to an ice bath. Squeeze out excess water and season with 1/2 tsp minced garlic, 1/2 tsp soy sauce, and 1/2 tsp sesame oil.

Heat 1 tbsp vegetable oil in a large pan or wok over medium-high heat. Stir-fry the sliced onions until translucent, about 2 minutes. Add carrots, bell peppers, and shiitake mushrooms, stir-frying for another 3-4 minutes until tender-crisp. Remove vegetables from the pan and set aside.

In the same pan, add another 1 tbsp vegetable oil if needed. Add the marinated beef and stir-fry until fully cooked and lightly browned, about 3-5 minutes. Remove the cooked beef from the pan and set aside with the vegetables.

In a small bowl, whisk together 4 tbsp soy sauce, 1 tbsp sugar, 2 tbsp sesame oil, and 1/2 tsp black pepper. This will be the main flavoring for your Japchae.

In a very large bowl or directly in the wok (if large enough), combine the cooked noodles, all the stir-fried vegetables, cooked beef, and seasoned spinach. Pour the prepared Japchae sauce over everything. Using your hands (with gloves) or tongs, gently toss all ingredients together until everything is evenly coated and well combined. Taste and adjust seasoning if necessary. Garnish with toasted sesame seeds before serving.