Japchae -- Korean Sweet Potato Noodle Dish (韓國粉絲）

This is my favorite Korean cold dish.   Based on the recipe a friend of mine gave me many years ago,  I made some changes according to my own tastes.  It doesn't taste exactly like the one served in the Korean restaurants, but my kids like it and my guests seem to like it too.  It is often made as a cold dish in my summer BBQ parties over the years.   The other day, my daughter called and asked me for its recipe.  So, I made it tonight and here it is.

Ingredients: 1. Sweet Potato Noodles- half a bag (There are all kinds of brands from Korea, China or Taiwan in Chinese markets.  Some noodles are thinner, some are thicker.  I like to buy thicker ones, see picture below for product package) 2. Two carrots, medium size 3. One medium onion 4. 8 dry mushrooms 5. 2 stalks of green scallion 6. Seasoning: soy sauce, oyster sauce, sesame oil, salt

Steps: 

1.  Cut off the stem from dried mushrooms, soften them in water for at least 30 minutes.  
2.  Shred carrots into strips (not too thin), cut onions, mushroom, and green scallion into strips.
3.  Add 3 TSB vegetable oil in a flat bottom cooking pan.  Stir-fry onion, carrots and mushroom until soft.  Add 1/2 tsp salt, 1 TSB soy sauce and 2 TSB oyster sauce.  Add green scallion at last and turn off the heat. This dish is supposed to be a bit sweet, oyster sauce adds to the taste of sweetness.
4.  Boil water in a big pot.  Put the sweet potato noodles in, when the water is boiling.  Cook for about 7-8 minutes (Or, follow instruction on the package).  The cooking time varies depending on the thickness of the noodle.
5. The sweet potato noodles are a bit chewy, which is expected.  Use a strainer to drain water from the pot, and cool the noodle with cold running water.  Pour noodle into a big bowl, season with 1 TSB sesame oil, 1/2 TSB soy sauce and 1/2 TSB oyster sauce.  Mix the noodle with the vegetables from Step 3.  Sprinkle some roasted white sesames before serving.  

With the ingredients above, I made two plates of japchae as shown in the picture.  It is plenty for a dinner of 6.  If you want to make it for a big party, you can double or triple the quantity of the ingredients.  The noodle tends to harden if you put it in the refrigerator,  a reason not to make too much.  In the original recipe I got, it also added some beef strips (marinate and stir-fry separately) and spinach leaves (boil them and mix).   I like to keep it a vegetarian dish.  Since spinach doesn't really add more favor, it's not used here.  The roasted sesames are for decoration only, it is optional.