Japchae is a well-known, and well-loved Korean dish. As far as I know, Japchae means 'mix everything'. Traditionally, this dish is served during festive seasons, or birthday parties, etc. It's a dish that incorporates a wide selection of vegetables (with beef or just vegetarian) with DangMyen (Korean style glass noodle[韩国冬粉,or韩国粉丝]). DangMyen, although looks similar to Chinese glass noodles, is slightly darker in colour. Aside from the colour difference, DangMyen is much more chewy (or Q-vy) in texture, due to the fact that it's made from sweet potato flour, instead of the ordinary flour.
It was a love at first bite for myself with this noodle dish. As a matter of fact, this is my most favourite Korean dish, having KimChee as first runner up. I often cook Japchae myself. Not only that it's a dish easy to master, it's a meal full of fibre and hence good for your health.

DangMyen. The package.

DangMyen. Before cooking. You'll have to cook the noodle in boiling hot water before frying with assorted vegetables.

The vegetables. Zucchini, Chinese eggplant (brinjal in Malaysia), green pepper (capsicum in Malaysia), onion, and spring onion (or scallions). Slice them before cooking-in-action.

The ingredients. Sliced onions, sliced zucchini, sliced green pepper, chopped spring onion (into lengthwise), sliced mushrooms, sliced Chinese eggplant, pre-cooked Dangmyen, and some shredded egg for garnish.
It's easy to cook. First, to your wok, add in some oil. Next, add in some garlic, and stir fry until the garlic turn golden brown and you get the aroma of garlic. If you're having meat as part of your ingredients, put them in after garlic, and stir fry.
You can then put in your vege one by one. The order that I usually go by: onion-> Chinese eggplant -> green pepper -> zucchini.

Stir frying in action.
When the veges are half-cooked, put in mushroom, and DangMyen. Keep on stir-frying.
The sauce? I give you, my new-found recipe:

LKK's Korean Barbecue sauce.
Previously I was only using normal soy sauce with dark soy sauce. But I always feel that I am missing something. So, one day, I incorporated this sauce into my Japchae, and oh boy, I was so delighted with the end result. The taste that I made is very similar to the one I had in
Hee Been (a great Korean restaurant that is closely nearby Washington D. C.).
Back to the method. Use LKK's Korean Barbecue sauce to taste. Depending on the amount of vege and Dangmyen you're using, a couple of spoonful sauce should suffice everyone's tastebud.
When the dish is almost ready, add in spring onion and keep on stir-fry for another minute or so.
The dish is often garnished with sliced eggs and sesame seeds.

I hope you'll like it.