This dish uses a root called duduk in Korean (it's called Codonopsis lanceolata or bonnet bellflower in English). It's related to doraji 도라지, which are also bellflower roots, except it is a different variety.
8 bonnet bellflower roots (duduk 더덕)
1/2 tsp hot pepper powder (gochugaru)
1/2 tsp hot pepper paste (gochujang)
2 tsp chopped scallions
1 tsp sesame powder
1 tsp sesame oil
1 tsp sugar
1 tsp garlic, minced
1 tsp corn syrup (mulyeot)
Using the blunt side of a knife, tenderly pound the bellflower roots (as you might a clove of garlic). Cut into bite-sized pieces.
Mix all of the ingredients (besides the bellflower roots).
Put one teaspoon of water in a heavy skillet and preheat on medium high heat.
Spread all the bellflower roots on the bottom of the pan in a single layer.
Spread the sauce over the roots and cook 15- 20 minutes on medium heat, covered.