Tom Kha Gai

Ingredients

Aromatics

• 10 slicesfresh galangal
• 3 stalkslemongrass, bruised and cut into lengths
• 8kaffir lime leaves, torn
• 3coriander roots, bruised
• 4shallots, bruised

Liquid

• 500 mlchicken stock
• 600 mlcoconut milk

Solids

• 500 gchicken thigh, sliced
• 200 gstraw or oyster mushrooms

Seasoning

• 4 tbspfish sauce
• 1 tbsppalm sugar
• juice of 3 limes
• 6to 10 bird’s eye chillies, bruised
• 2 tbspnam prik pao, roasted chilli paste, optional

To finish

• a large handful coriander leaves
• sliced red chilli

To serve

• with steamed jasmine rice

Directions

1. Slice it thinly across the grain, and it is not eaten but left in the bowl. Tear the kaffir lime leaves rather than cutting them, and remove the tough central rib. Bruise the chillies too rather than slicing them, which gives fragrance and moderate heat without making the soup fierce.
2. Bring the stock to a simmer with all the aromatics and let them infuse for ten minutes before anything else goes in. The kitchen should smell strongly of lemongrass and galangal before you continue.
3. Add the coconut milk and bring it back only to a bare simmer. Never let coconut milk boil hard, since it splits into oil and grainy curds and cannot be brought back. Keep it barely trembling from this point onward. Use full-fat coconut milk, since low-fat versions are thin and split more readily.
4. Add the sliced chicken and poach it gently for five to seven minutes until just cooked. Poach it rather than boiling it, which keeps it tender in a soup this delicate. Add the mushrooms for the last three or four minutes. Add fish sauce for salt and palm sugar for sweetness while it simmers.
5. Add the lime juice off the heat, at the very end, and never during cooking. It should be sour, salty, sweet and hot at once, with the sourness and saltiness leading. Adjust in small amounts: more fish sauce for salt, more lime for sourness, more sugar to round it.
6. Keep tasting until it makes you want another spoonful, which is the only real test. It is a roasted chilli paste with shallot, garlic and tamarind, sweet and smoky rather than fiercely hot.
7. Scatter coriander leaves over off the heat and add a few slices of fresh red chilli. Warm it gently if you must, and add a fresh squeeze of lime before serving.

Technique

• Galangal is not ginger and the dish is named after it.
• The aromatics are left in the bowl and not eaten.
• Lime juice goes in off the heat or it turns flat and bitter.

Substitutions

• Frozen galangal, which works perfectly well.
• Prawns or tofu in place of chicken.

Variations

• Tom kha het, made with mushrooms alone.
• With nam prik pao stirred in, for the orange version.
• Made with prawns, as tom kha goong.

Frequently asked questions

What is Tom Kha Gai?

Tom Kha Gai is a soup & stew from Thailand: silky coconut chicken soup soured with lime and galangal.

How long does Tom Kha Gai take to make?

Tom Kha Gai takes 20 min of preparation and 25 min of cooking. The recipe makes 4 servings. It is rated easy to make.

What can I substitute in Tom Kha Gai?

Yes, within limits. Frozen galangal, which works perfectly well. Prawns or tofu in place of chicken.

What is the most important thing to get right in Tom Kha Gai?

Slice it thinly across the grain, and it is not eaten but left in the bowl. Tear the kaffir lime leaves rather than cutting them, and remove the tough central rib. Bruise the chillies too rather than slicing them, which gives fragrance and moderate heat without making the soup fierce.