One of the most under-appreciated gems in the tea world, the refined flavour and meticulous production of Korea's sejak variety make it a tea worth discovering. 
 
Picked just after the first flush of spring, sejak tea is crafted from tender young leaves, hand plucked from the lush tea gardens of Boseong and Jeju Island. Sejak's subtle complexity is often described as smooth, vegetal and nutty, with hints of pine and chestnut.
 
The unique production method combines light steaming with gentle pan-firing, preserving the tea's vibrant green colour and mellowing any bitterness.

How to serve

Brew sejak at 75°C for two minutes to bring out its gentle sweetness.
Reinfuse the leaves for a second, slightly longer steep to savour its evolving character. The second infusion often reveals richer chestnut notes and a hint of seaweed.

Where to buy

Postcard Teas sells 20g of sparrow's tongue sejak tea for £9.50 (020-7629 3654; www.postcardteas.com)

Jonathon Jones tastes tea and exports English-grown tea worldwide.