What You're Handling
Kohila (Lasia spinosa) is a marsh plant in the arum (Araceae) family — the same family as taro and elephant yam. The edible part is the young shoot and the underground rhizome. Its Latin name is the clue: spinosa means "spiny."
Two separate things make raw kohila unpleasant, and they are handled differently:
- The spines and hairs — a mechanical problem. The leaf stalks and stems are covered in sharp spines, and the outer skin carries fine, stiff prickly hairs. These scratch and irritate skin on contact and are unpleasant to swallow. You remove them by peeling and scraping.
- Calcium oxalate — a chemical irritant. Like other Araceae, raw kohila can hold needle-like calcium oxalate crystals that cause a sharp, stinging sensation in the mouth and throat. Cooking is the sensible precaution, which is why kohila is always cooked.
Step-by-Step Prep
1. Wear Gloves
The spines and hairs will scratch your hands, and the irritation can linger. Disposable gloves are ideal; if you have none, work carefully and handle the stalks by the leafy end rather than gripping the spiny shafts.
2. Strip the Leaves
Cut away and discard the large, arrow-shaped leaves and any tough outer leaf bases. The stalks and the tender core are what you keep.
3. Remove the Spines and Hairs
This is the step that decides whether kohila is pleasant or prickly:
- Run a knife down each stalk to shave off the spiny ridges and any stiff hairs.
- Peel the fibrous outer skin with a knife or firm vegetable peeler, pulling away every spine and bristle. The interior should be pale and smooth.
- Scrape stubborn patches rather than leaving even a few spines behind — they will survive cooking.
4. Slice, Then Soak
Cut the peeled stalks and rhizome into thin rounds, half-moons, or julienne strips. Soak the slices in cold water for 15–30 minutes, changing the water once. This removes excess starch and softens any residual edge.
5. Cook Thoroughly
Raw kohila is not food. Cook it until tender:
| Method | Time | Notes |
|---|---|---|
| Boil / par-boil | 8–10 minutes | Before adding to a stir-fry or curry |
| Simmer in coconut-milk curry | 15–20 minutes | Until tender, no raw crunch left |
| Stir-fry | 5–7 minutes | After par-boiling |
The test: a piece should be tender all the way through, with no chalky, raw, or stinging sensation. If there is any tingle or firmness, cook longer.
If You Get Scratched or Stung
- Spines/hairs on skin: rinse with cool water and wash with soap. The fine hairs can embed like splinters — pull out any you can see with tweezers.
- Irritation after eating raw kohila: rinse your mouth and drink water. Seek medical attention if your throat swells, or if you have difficulty breathing or swallowing.
- Wash your hands and tools before touching your face or eyes.
How It's Traditionally Eaten
Once peeled and cooked, kohila has a mild, earthy flavour and a dense, slightly crunchy bite — a firmer cousin of bamboo shoot or lotus stem. In Sri Lanka it appears as:
- Kohila curry — simmered in spiced coconut milk with curry leaves and chilli
- Kohila sambol — finely sliced, cooked, then tossed with grated coconut, chilli, onion, and lime
- Stir-fries — quick high-heat dishes with onion and tempering spices
Common Mistakes
- Peeling bare-handed — the spines and hairs scratch, and the irritation lingers.
- Leaving spines or hairs behind — they do not soften with cooking; remove every one.
- Eating it raw or merely blanched the once — calcium oxalate needs real cooking to break down. Never taste a raw piece.
- Undercooking into a chalky centre — cook until tender all the way through; when in doubt, cook longer.
- Skipping the soak for a fry — a cold-water soak keeps the texture clean and reduces residual edge.
Prepared this way, kohila is a mild, versatile vegetable — the preparation is careful, but it is simple, and the result needs nothing more than coconut, chilli, and a little salt.
