Rehydrating dried chillies
Also called soaking chillies, reconstituting chillies
Quick answer
Soaking toasted dried chillies in hot water until soft enough to purée — the step between the dried pod and a mole, adobo or chilli paste.
What it does to spices
Soaking returns water to the dried flesh so that it purées into a smooth, thick paste, which is how a dried chilli comes to season and thicken a sauce at once. Some of what the chilli carries leaves with the water — sugars, some colour, and bitterness from any over-toasted skin — while the heat and most of the colour stay in the flesh, because capsaicin and the carotenoid pigments dissolve in fat rather than water. Cooks therefore decide case by case whether to use the soaking liquid or discard it: sweet and fruity pods give a useful liquid, scorched ones a bitter one.
Why it works
Dried chilli tissue absorbs water back into its cells, softening the walls so they break down in a blender. Water-soluble sugars and flavour compounds diffuse into the soaking water; capsaicin, which is almost insoluble in water, and the fat-soluble red carotenoids stay largely in the flesh.
How it goes wrong
- Soaking in boiling water for too long, which draws out bitterness and dulls the fruit.
- Soaking chillies that were burned in toasting — the bitterness passes into both flesh and liquid.
- Leaving the tough skins unblended or unstrained, which makes a mole gritty.
Spices it matters for
What it changes in the spice
The chemistry this technique sets off, explained in full on the science page.
Where it is used
The pairings that specifically call for this technique.
- Ancho with pork — Adobo and the slow-braised pork traditions of central Mexico. Ancho gives body as well as flavour — a rehydrated pod purées to a thick paste — so it seasons and thickens a braise at once, which is why the sauce clings rather than pooling.
- Guajillo with beef — Birria and the red adobos are the documented case, and the mechanism is acidity against fat. Long-braised beef is rich and needs something tart cutting it, and guajillo supplies that along with the clear red colour these dishes are recognised by — a job ancho cannot do, which is why the two go in together with guajillo leading.
- Mulato with turkey — Mole poblano over turkey is the dish this chilli exists for, and the pairing is structural rather than incidental: turkey is lean and mild, and a sauce built on thick-fleshed sweet chillies supplies the fat-carried richness and body the bird has none of. Mulato is the darkest of the three chillies in that sauce.
- Mulato with pork — Adobos built on thick-fleshed dried chillies are a standing treatment for pork, and mulato brings sweetness and body to a long braise where a hotter chilli would only bring heat. The sauce thickens on the rehydrated flesh rather than on flour or reduction.
Questions this page answers
- how to rehydrate dried chillies
- should I use the chilli soaking water
- soaking ancho chillies