Ca Kho To

Ingredients

Fish

• 800 gcatfish or another firm fish, in thick steaks
• or pork belly, for thit kho

Marinade

• 3 tbspfish sauce
• 2 tbspsugar
• 4 clovesgarlic, minced
• 3shallots, minced
• 1 tspblack pepper, coarsely ground

Caramel, nuoc mau

• 100 gsugar
• 2 tbspwater
• 3 tbsphot water, for stopping it

To braise

• 2 tbspoil
• 200 mlcoconut water or water
• 1 tbspfish sauce
• 2red chillies
• a thumb of ginger, sliced
• plenty of coarsely ground black pepper

To finish

• 2spring onions, in lengths
• more black pepper

To serve

• plain steamed rice
• canh, a clear soup
• boiled or pickled vegetables

Equipment

• a clay pot, to, if you have one

Directions

1. Put the sugar and water in a small heavy pan over a medium heat and let it dissolve without stirring. Do not stir once it boils, since stirring encourages the sugar to crystallise into grains.
2. Swirl the pan gently if it colours unevenly. Let it darken through gold to amber to a deep reddish brown, which happens slowly and then very fast. Take it off the heat when it is dark and just beginning to smoke faintly and smell slightly bitter. Now the dangerous part, which needs care.
3. Add the hot water to stop the caramel, standing well back and pouring it down the side of the pan. Molten sugar is far hotter than boiling water and it sticks to skin, so keep your face and hands clear and use a long-handled spoon.
4. Use hot water rather than cold, which reduces the violence of the reaction considerably. Swirl it back together over a low heat until smooth. It keeps for months in a jar, so it is worth making a larger batch.
5. Use thick steaks on the bone rather than fillets, since bone and skin add body and stop the fish falling apart. Marinate it with fish sauce, sugar, garlic, shallot and pepper for thirty minutes. Heat oil in the pot and brown the fish pieces briefly on both sides.
6. Add the caramel, coconut water, fish sauce, ginger and chillies to the pot. The liquid should come about halfway up the fish rather than covering it.
7. Bring it to a simmer, then lower the heat until it is barely bubbling and cover it partly. Never boil it, since the fish breaks apart and the caramel scorches on the base. Simmer for thirty to forty minutes. Spoon the liquid over the fish occasionally rather than stirring it, which would break up the pieces.
8. Turn the pieces once, very carefully, halfway through. Now the reduction, which is what the dish is about. Uncover it for the last ten minutes and let the liquid reduce to a thick dark glaze. Keep reducing until it clings to the fish and there is only a few spoonfuls left in the pot. A watery ca kho has not been reduced far enough, and the concentration is the whole point.
9. Grind a great deal of coarse black pepper over at the end. Pepper is a defining flavour in kho dishes and it should be assertive rather than a background note. Scatter spring onions over and serve it in the pot. Serve it with plenty of plain rice and a clear soup alongside, since the fish itself is very strongly flavoured. It is genuinely better the next day and it keeps three days refrigerated.

Technique

• The caramel must go dark and slightly bitter, or the dish is merely sweet.
• Adding water to hot caramel erupts violently, so use hot water and stand back.
• It is reduced to a thick glaze and eaten in small amounts with plain rice.

Substitutions

• Pork belly in place of fish, as thit kho.
• A heavy cast iron pot in place of a clay pot.

Variations

• Thit kho trung, with pork belly and eggs.
• Made with mackerel or salmon.
• With more chilli, for a hotter version.

History

Fish braised in caramelised sugar and fish sauce in a clay pot, a Mekong delta home dish eaten with plain rice and soup.

Frequently asked questions

What is Ca Kho To?

Ca Kho To is a main from Vietnam: catfish caramelised in a clay pot with fish sauce and pepper. Fish braised in caramelised sugar and fish sauce in a clay pot, a Mekong delta home dish eaten with plain rice and soup.

How long does Ca Kho To take to make?

Ca Kho To takes 20 min plus 30 min marinating of preparation and 45 min of cooking. The recipe makes 4 servings. It is rated medium to make.

What can I substitute in Ca Kho To?

Yes, within limits. Pork belly in place of fish, as thit kho. A heavy cast iron pot in place of a clay pot.

What is the most important thing to get right in Ca Kho To?

Put the sugar and water in a small heavy pan over a medium heat and let it dissolve without stirring. Do not stir once it boils, since stirring encourages the sugar to crystallise into grains.