http://www.maangchi.com/recipe/dotorimukmuchim Check out the written recipe, tips, photos, and some funny stories about this dish on my website please!
Ingredients:

For dotorimuk

½ cup acorn jelly powder (dotori mukgaru)
3 cups water
½ ts salt
For the seasoning sauce

⅓ cup soy sauce
2 ts honey or sugar
3 garlic cloves, minced
3 stalks of green onions, chopped
1 tbs hot pepper flakes
1 tbs and 2 ts toasted sesame oil
1 tbs toasted sesame seeds, add right before serving so they don't lose their crispiness
garnish with shredded red pepper (shilgochu)
For the vegetables, you can use

2 cups lettuce cut into bite size pieces
¼ cup onion, sliced thinly
1 cup's worth edible chrysanthemum (ssukgat), cut into bite size
3-5 perilla leaves, chopped
2 tbs worth carrot, shredded
½ cup's worth cucumber, thinly sliced
1 red chili pepper, chopped
1 green chili pepper, chopped

In a large bowl, combine all the ingredients for dotorimuk. Stir with a wooden spoon and strain to remove any lumps. Pour the mixture into a thick bottomed pot and stir over medium heat about 7-8 minutes until it bubbles.
Lower the heat and stir another 5 minutes.
Pour the mixture into a rectangular glass container and let it cool down.
Put it into the fridge for about 4-7 hours until it's solid.
Create the seasoning sauce by combining soy sauce, sugar or honey, hot pepper flakes, garlic, and sesame oil in a mixing bowl. Set aside.
Take the acorn jelly out of the fridge. Turn the glass container upside down over your cutting board so the solidified jelly slides out in one piece. Cut into bite sized pieces 2 inch x 1 inch and ¼ inch thick.
*tip: Use a crinkle cutter to make a nice wavy pattern on each piece of jelly
Put all the vegetables in a large bowl. Mix with the seasoning sauce by hand.
Add the dotorimuk and gently mix it all together.
Transfer to a serving plate. Sprinkle sesame seeds over top and serve.