Kol Posola

The pale inner pith of the banana stem, sliced into rounds and stripped of its threads, then cooked down dry with black gram, mustard seed, and fenugreek

Origin: Guwahati & the Brahmaputra Valley

From the journey of Banana.

Assam eats the banana plant more completely than anywhere else in India. The fruit is fruit, the flower is a vegetable, the leaf is a plate and a wrapper for patot diya fish, the peel and the trunk are burnt for khar, and the pseudostem, which is not a trunk at all but a tight cylinder of leaf sheaths, is cut open for the pale core at its centre. That core is posola. It is sold in the markets of the valley as a peeled white baton, and preparing it is a small ritual. The rounds are sliced thin, and as each one is cut it is twisted against the next so that the long transparent fibres lift away and can be pulled off in threads, which is the difference between a dish that is tender and one that is upholstery. The slices go straight into salted water, because the cut surfaces brown within minutes. Then it is cooked plainly, as most Assamese vegetables are: mustard oil taken to smoking, mustard seed, fenugreek and cumin, onion, garlic, green chilli, soaked black gram for body, and no tomato, no cream, and very little spice beyond that. It is simmered until the water has gone and finished dry. The other version puts it in khar, the alkali made from the ashes of the same plant, which is as close to a self-contained dish as cooking gets.

Ingredients

Vegetable

  • 600 g banana pseudostem (posola), outer sheaths removed, the pale core only
  • 1 tbsp salt, for the soaking water
  • 60 g black gram (mati dal), soaked for 2 hours and drained

Tempering

  • 3 tbsp mustard oil
  • 1 tsp black mustard seeds
  • 0.5 tsp fenugreek seeds
  • 1 tsp cumin seeds
  • 1 onion, finely sliced
  • 4 garlic cloves, crushed
  • 3 green chillies, slit
  • 0.5 tsp ground turmeric
  • 1 tsp salt
  • 300 ml water

Method

  1. Slice the pith into thin rounds. After every two or three slices, twist the cut rounds apart and pull away the long clear fibres that come with them, then drop the slices into the salted water.
  2. Drain the slices and chop them roughly.
  3. Heat the mustard oil until it smokes, take it off the heat for a moment, then add the mustard, fenugreek, and cumin seeds and let them crackle.
  4. Add the onion, garlic, and green chillies and cook for four minutes, until the onion is soft and pale gold.
  5. Add the drained pith, the soaked black gram, the turmeric, and the salt, turn everything over, then pour in the water and bring to a simmer.
  6. Cook uncovered for 18 to 20 minutes, until the gram is tender and the pan is almost dry.
  7. Serve warm with rice, at the start of the meal rather than the end of it.

Notes

Banana pith is sold as vazhaithandu or banana stem in South Asian grocers, often already trimmed. Use it the day you buy it. For the khar version, leave out the mustard seeds and add three tablespoons of khar, or a quarter teaspoon of bicarbonate of soda, in the last five minutes.

The Gastrographer

The Gastrographer

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Ingredient originTrade or transit route
Became a culinary stapleColonial / trade control
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