Hansot Dosirak 한솥도시락

Hands down, the best take out place in Wangsimni (advertised like this by many locals).
Price ranges from round about 2k to 10k Won, Meat, Rice and Vegetables as well as salads available. Total different products way over 50 = big variety.
Good and fast service (a lot of things prepared, most meals are done after 2,3 minutes).
Also, some instant soups (to make at home) and cold drinks can be bought.

3-33 Haengdang-dong, Seongdong-gu, Seoul, South Korea