-
1
Dry-roast the cumin and coriander seeds separately in an ungreased pan over medium heat, shaking continuously, until each releases its fragrance and deepens one shade in colour — doing them apart prevents the smaller coriander seeds from scorching before the cumin is ready. Remove immediately and allow to cool before grinding both to a fine powder in a mortar or spice grinder. The smell should be toasted and sharp, not acrid.
-
2
Pound the drained chillies with the salt in the mortar, working until a coarse paste forms with no visible skin fragments remaining — the salt acts as an abrasive that helps the pestle tear through the tough skins rather than simply compressing them. The mass should be dark red and tacky rather than wet.
-
3
Add the lemongrass and pound to full incorporation, then add the galangal, coriander root, and kaffir lime zest in sequence, each pounded to smoothness before the next is introduced — adding the fibrous aromatics one at a time gives each ingredient time to be broken down fully, so the finished paste does not carry strands that would resist the pestle once the mass grows larger and harder to work. The paste should be cohesive and hold together when pressed.
-
4
Add the shallots and garlic and continue pounding — their moisture will loosen the paste initially, but keep working so that liquid is driven back into the mass rather than pooling around it. Pound until the paste tightens again and no fibrous strands remain; the surface should be uniform in colour and texture.
-
5
Add the roasted shrimp paste and the ground spices and pound until fully absorbed — the shrimp paste needs to be worked in thoroughly so its salt and depth are distributed evenly rather than sitting in pockets that will make the final curry uneven in flavour. The paste will darken further and the smell will shift from sharp and raw to deep and fermented-spiced.
-
6
This is where the dish lives or dies. Add the ground roasted peanuts in two additions, pounding each into complete, fine incorporation before the next — introducing them gradually keeps the mass workable and prevents loose peanut from skating around the mortar unworked, which is what leaves graininess in the finished paste. Press a small amount between two fingers: it should feel solid and uniform, with no grit; any coarseness means the paste has not been worked sufficiently and will break the final curry's structure.
-
7
Work the finished paste briefly with the pestle to consolidate it, so any last separation between the peanut oil and the aromatic base is pressed back together into a single dense mass. It should be significantly drier and more concentrated in volume than a standard red curry paste — it will not spread or flow when a spoonful is turned out, but hold its shape. Taste for salt, then use immediately or store covered.