Eastern Nepal Food: Tongba, Kinema and Yangben

In the hills of eastern Nepal, the year has a hungry season. Before roads and refrigerators, families had to keep the harvest of summer through the long dry winter, and fermentation was how they did it. Soybeans became kinema, leafy greens became gundruk, radish roots became sinki, and millet became tongba. These foods are still at the centre of the Rai, Limbu and wider hill kitchen, and they give eastern food its sour, pungent, deep flavours.

You will also meet dishes found everywhere in Nepal: dal bhat, sel roti, dhido and momo. But the east does them its own way, with more pork, more ferments, more fire from the chillies and more millet. In the high valleys of Taplejung and Sankhuwasabha, food turns Tibetan, with butter tea, tsampa and potatoes. On the plains around Biratnagar and Koshi, rice, fish and lentils rule.

This guide tells you what to look for, what it tastes like, and where we take our guests to try it.

These are the foods we think best tell the story of the east. Some are everyday, some are festival food, and a few are acquired tastes. Try them all at least once.

Tongba is the drink most visitors remember. Cooked millet is mixed with a starter cake called marcha and left to ferment for days or weeks. To serve it, the fermented grain is packed into a tall vessel, traditionally of wood or bamboo, now often of aluminium, and topped up with hot water. You sip the warm, mildly alcoholic liquid through a bamboo straw closed at the bottom and slit at the sides, so the grain stays in the pot. When the liquid runs low, your host adds more hot water, and one pot can last an evening.

Tongba is more than a drink. In Limbu households it is offered to guests and to ancestors, and it plays a part in weddings, funerals and festivals. Hile is the most famous place to drink it, and its small bhatti, family-run bars, serve it with sukuti, potato achar and fried soybeans. Drink slowly. It is gentle at first but adds up, especially at altitude.

Kinema is the soybean ferment of the eastern hills, especially linked with the Limbu. Soybeans are soaked, boiled, crushed a little, wrapped in leaves and kept warm for two or three days, until they turn sticky and smell strongly of ammonia. Cooked with onion, tomato, garlic, chilli and turmeric, kinema becomes a rich, savoury curry eaten with rice or dhido. It is similar to Japanese natto, and food scientists have studied it as one of the Himalaya's traditional ferments.

Yangben is a Limbu speciality few outsiders know. It is a lichen gathered from the forest, washed, boiled and cooked with pork and spices into a dish with a chewy texture and an earthy flavour. It is mostly cooked at home, so the best way to try it is in a Limbu homestay or with a guide who can ask a family to make it. The Limbu kitchen also uses millet, buckwheat, pork, bamboo shoots and wild greens in ways that differ from valley to valley.

Gundruk is made all over the Nepal hills, but in the east it is a daily food. In autumn, when mustard, radish and cauliflower leaves are plentiful, families wilt the leaves, pack them tightly into an earthen pot or a pit lined with straw, and leave them to ferment for a week or more before drying them in the sun. The dark, crumbly result keeps for months. Soaked and cooked with tomato, chilli and a little soybean, it makes a sour, warming soup that is served alongside dal bhat on cold days.

Sinki is the same idea applied to radish roots. The roots are cut, fermented in a pit and sun-dried into hard, pale strips. In winter, when fresh vegetables are scarce, sinki goes into soups and curries and gives them a sharp, almost pickled flavour. If you see bundles of dried leaves or strips hanging under the eaves of a farmhouse, ask your host what they are; the answer is usually the start of a long conversation about food and seasons.

Ilam is the place for tea, and for the foods that go with it. Its orthodox teas range from light, floral first flush in spring to round, sweet autumn tea in October and November. Visit a small factory and taste side by side before you buy.

Ilam is also dairy country. Soft chhurpi, a fresh cheese, goes into curries and achar, while hard chhurpi, dried until it is like a stone, is chewed slowly for hours and sold in strings in the bazaar. And Ilam is home to the Akabare chilli, a small round chilli of fierce heat, pickled whole or crushed into achar. One small bite is enough for most visitors.

Millet is the grain of the eastern hills. Finger millet, kodo in Nepali, grows on steep terraces where rice will not, and it ends up in tongba, in kodo ko roti, a dark, dense flatbread, and in dhido, a thick porridge eaten with the fingers alongside gundruk and meat. Buckwheat and maize are used the same way higher up.

At festivals, the food changes. At Dashain and Tihar, families fry sel roti, ring-shaped breads of rice flour that are crisp outside and soft inside, and meat is shared with relatives. At Sakela and Chasok, Kirat households prepare pork, chicken, tongba and rice, and the first grain of the new harvest is offered before anyone eats. Visit in these weeks and you may be pressed to eat far more than you planned.

On the Kanchenjunga and Makalu treks, lodge menus are short: dal bhat, noodles, fried potatoes, Tibetan bread, porridge and tea. In Ghunsa and other high villages you may be offered butter tea, salty and rich, and tsampa, roasted barley flour mixed with tea or butter. Dal bhat is the best fuel for walking, and refills are usually free.

On the plains of Jhapa, Morang and Sunsari, the food is closer to that of the wider Terai, with rice, lentils, fish curry and seasonal vegetables. Near Koshi Tappu, fish from the river is fried at roadside stalls. Dharan, between hills and plains, is famous for its markets and for pork dishes of every kind. Eastern Nepal is also one of the world's main sources of large cardamom, grown in the shade of forest trees across Taplejung, Ilam and Panchthar.

• Eat dal bhat in the middle of the day, the way locals do; it is fresh, filling and usually refilled for free.
• Ask your guide to arrange a meal in a family kitchen; many Kirat dishes are rarely sold in restaurants.
• Say if you do not eat pork, beef or alcohol; hosts will cook accordingly without fuss.
• Go slowly with ferments and tongba if your stomach is not used to them, and drink treated water.
• Buy tea, hard chhurpi and dried chillies to take home; they travel well.