[2] The caffeine-free infusion is a popular hot drink in winter.

[3] In Gangwon Province, the tea is called gangnaengi-cha (강냉이차)—gangnaengi is a Gangwon dialect for "corn"—and is consumed throughout late autumn and winter in most households.

[4] Traditionally, corn kernels are dried and roasted to prepare oksusu-cha.

[2] The roasted corn kernels are then boiled in water until the tea turns yellow.

Although the drink is naturally sweet, sugar is sometimes added when a sweeter flavor is desired.