Steps

1. In a bowl, combine Soy Sauce 2 tbsp, Cooking Sake (Rice Wine) 2 tbsp, Mirin (Sweet Rice Wine) 2 tbsp, Sugar 1.5 tbsp, and Chicken Bouillon Powder 1 tsp.
   🕒 00:20
2. Add Potato Starch 3 pinches to the [A] sauce and mix well to avoid lumps. (Secret Tip!) Adding potato starch allows the sauce to coat the noodles exceptionally well.
   🕒 00:45
3. In a separate bowl, combine Soy Sauce 1/2 tbsp, Cooking Sake (Rice Wine) 1/2 tbsp, Sugar 1/2 tbsp, and Grated Garlic 1 tsp. Mix well until dissolved.
   🕒 01:01
4. Cut 1/2 Onion in half lengthwise, then thinly slice it into 5mm strips. (Secret Tip!) Since the glass noodles are thin, make sure not to cut the onion too thickly.
   🕒 01:33
5. Trim the ends of 1/3 Carrot (approx. 70g). Keep the peel on for flavor and nutrients. Once stable, slice into 5mm strips, stack them, and julienne. (Secret Tip!) The peel contains flavor and nutrients, so do not remove it.
   🕒 01:56
6. Remove the stems and seeds from 2 Bell Peppers. Lightly crush them with your palm, then julienne them to the same thickness as the other vegetables. (Secret Tip!) Lightly crushing the bell peppers reduces their surface unevenness, making them easier to slice evenly.
   🕒 02:42
7. Thoroughly pat dry the surface of Thinly sliced beef 120g with paper towels. (Secret Tip!) Patting the beef dry helps the marinade penetrate the meat better.
   🕒 03:17
8. Add the [B] marinade to the dried beef and knead well until no moisture remains.
   🕒 03:31
9. Bring a pot of water to a boil. Once boiling, add Glass Noodles (made from mung bean starch) 65g and cook for 2.5 minutes until slightly firm. (Secret Tip!) Mung bean starch noodles hold their chewiness even when cooked, making them ideal for Japchae.
   🕒 03:54
10. Drain the cooked glass noodles in a colander and drain them thoroughly without rinsing with water.
    🕒 04:20
11. Heat a little oil in the same frying pan over medium-low heat. Once warm, add the julienned Onion and Carrot and stir-fry.
    🕒 04:26
12. Add a pinch of Salt to the stir-frying vegetables and cook until the onion becomes translucent.
    🕒 04:44
13. Once the onion is translucent, add the julienned Bell Peppers and stir-fry until coated with oil and shiny. (Secret Tip!) Adding the bell peppers later prevents them from becoming too soggy and helps retain their texture.
    🕒 04:54
14. Once the vegetables are stir-fried, remove them from the pan.
    🕒 05:06
15. Add a small amount of Sesame Oil to the same frying pan (without washing it) for added flavor, and heat over medium-low heat.
    🕒 05:12
16. Once the oil is warm, add the marinated beef and stir-fry until about 80% cooked, browning it as you go.
    🕒 05:21
17. Once the beef is cooked, remove it from the pan.
    🕒 05:33
18. Without washing the pan, add the [A] sauce (after mixing it well) to the pan with the remaining beef drippings, and heat over low heat.
    🕒 05:39
19. Stir the sauce while warming it over low heat. (Secret Tip!) Heat while stirring continuously to prevent the potato starch from clumping.
    🕒 05:50
20. Once the sauce is warm, add the drained glass noodles and toss to coat the noodles thoroughly with the sauce. Increase heat to medium-low.
    🕒 05:58
21. Stir-fry the noodles until the sauce is absorbed and the liquid has evaporated. (Secret Tip!) By allowing the noodles to absorb the sauce, the overall flavor becomes more concentrated and less diluted.
    🕒 06:09
22. Once the sauce has been absorbed, add the stir-fried vegetables and beef and toss briefly to combine everything.
    🕒 06:18
23. Drizzle with Sesame Oil 2 tsp for aroma and stir briefly. (Secret Tip!) The aroma of sesame oil easily dissipates with heat, so adding it at the end maximizes its fragrance.
    🕒 06:31
24. Transfer to a serving dish and it's ready to be enjoyed!
    🕒 06:43