Tum Kha Mu (ตำข่าหมู)

A Dish That Lives in Mortars, Not Cookbooks

One honest note before the recipe: you will not find ตำข่าหมู published as a single written recipe on Thai cookery sites. It is a northern kitchen and market dish — boiled trotter and a pounded-galangal dressing — that exists as two well-documented halves. The trotter half appears in every Thai trotter recipe: simmer the foot for an hour with galangal, lemongrass and kaffir lime until the meat gives. The dressing half is ตำข่า, the pounded young-galangal salad that Thai home cooks publish on their own pages. This recipe is those two halves joined the way northern cooks join them — and the sources for both halves are cited below, with no invented middle.

Read the Thai sources and the character of the dish is consistent. In a ตำข่า video from a northern cook, the method is laid out in four bare lines: pound the chillies and garlic to a paste, add the young galangal and pound just until it cracks, season with fish sauce, lime and fermented fish sauce — or shrimp paste, if that is what the kitchen has. A Lemon8 cook's written recipe for the same salad adds the warnings that matter: pound the galangal lightly, or it goes mushy and เฝื่อน — bitter and raw-tasting — and use young galangal, which is softer and sweeter than the woody old root.

The pork half comes from the trotter pot. Kapook's trotter recipe simmers the foot with galangal, lemongrass and kaffir lime for an hour, skimming the scum, and only ever adds the lime at the very end, off the heat. That end-lime rule is the one northern cooks keep when the warm meat meets the dressing: sour goes on last, or it cooks away.

The Recipe (trotter boil from Kapook; ตำข่า dressing from the Lemon8 and Facebook cooks)

The galangal. Every Thai source is firm that this is a galangal dish, not a ginger one. Lemon8's cook slices it as thin as she can and insists on young galangal; the ครัวง่ายๆ ครัวบ้าน version goes further and uses whole tender galangal stalks (ลำต้นข่า) as the body of the salad. The heat. Lemon8's mild version starts at two or three prik jinda chillies; the northern video pounds a proper handful. Both keep the chilli pounded with the garlic, not chopped in at the end.

The Method

1. The trotter. Wash the foot well, then simmer it in plenty of water with the galangal slices, lemongrass and kaffir lime leaves, plus the pinch of salt. Kapook's rule is an hour at a gentle bubble, skimming the foam so the broth stays clean. It is done when the meat comes off the bone with a tug.
2. The tearing. Lift the trotter out, discard the bones and the simmer aromatics, and tear the meat into bites while it is still warm. Warm meat takes the dressing the way cold meat does not — that is why the northern pot is kept on the back of the stove.
3. The pounding. In a mortar, pound the chillies and garlic to a paste. Then add the sliced young galangal and pound lightly — just until it cracks and the scent comes up. Both Thai sources agree: the galangal must stay in pieces. Over-pounded, it turns mushy and bitter (เฝื่อน), and the dish is ruined.
4. The seasoning. Stir in the fish sauce — and the fermented fish sauce if you are using it — then the lime juice and the half teaspoon of palm sugar. Taste the way the sources do: sour leads, salt follows, the chilli heat finishes at the back. The lime goes in last, never over heat.
5. The toss. Fold the warm trotter meat through the dressing with the shallots, kaffir lime slivers, and — if using — the dried shrimp and roasted peanuts. Scatter the herbs over the top and serve with a plate of cabbage, cucumber and long beans, or let everyone wrap mouthfuls in leaves, miang-style, the way the ครัวง่ายๆ cook serves hers with bai mayom.

Where Thai Sources Disagree

How Western Versions Get It Wrong

• Ginger instead of galangal. The dish is named after the galangal. Ginger is a cousin with none of the same pine-and-camphor perfume, and every Thai source insists the galangal — young, sliced thin — is the point of the salad, not a background note.
• No mortar. ตำ means pound. Dressing the meat with a whisked vinaigrette of galangal and lime makes a fine lunch, but it is not this dish. The pounding bruises the galangal and chilli together so the oil and the sharpness run into the dressing — that is the technique the dish is named after.
• The pulled-pork treatment. Western recipes turn trotters into slow-cooked, shredding braises and then dress them cold. Thai sources boil the foot for an hour in an aromatic pot and dress the meat while it is warm. Cold, the meat sits; warm, it drinks.
• Lime early, heat on. Kapook's trotter recipes add lime only after the pot is off the fire. Lime cooked even briefly turns thin and soapy. The dressing is always finished cold, in the mortar.
• Pounding the galangal to paste. The one failure every Thai source warns about, in almost the same words: over-pound the galangal and it goes mushy and เฝื่อน — bitter, raw-tasting, astringent. Crack it, do not crush it.

UK Ingredient Notes

• Pork trotters: a proper butcher will split one lengthwise for you; many Asian and Polish grocers carry them frozen. If you cannot face the trotter, a piece of pork shank or cheek boiled the same way is a respectable stand-in — the dressing is the dish's signature.
• Young galangal (ข่าอ่อน) is seasonal even in Thai grocers. Use the youngest, pinkest galangal you can find and slice it paper-thin across the grain; old roots stay woody.
• Fermented fish sauce (ปลาร้า): bottled versions at Thai grocers, including the common Thai-branded bottles. Go easy — it is far stronger than fish sauce.
• Dried shrimp and roasted peanuts: any Thai or East Asian grocer; both are optional but they give the salad the crunch the sources like.
• For miang-style wrapping, bai mayom (star gooseberry leaves) do not exist in UK shops; use chaphlu if you can find it, or Little Gem lettuce leaves — the Lemon8 cook's own fallback is "whatever vegetables you have".

Sources

No single Thai site publishes this dish under one name; it is assembled here from the two halves the sources actually document — the trotter boil and the ตำข่า dressing — and the joins are marked above. Where the sources disagree, we've said so.