Why dried chiles need preparation
Dried chiles are tough, leathery and often dusty, with stems and seeds that can make a sauce gritty or bitter. Before they go into a mole, adobo or red salsa, cooks usually clean them, toast them briefly and soften them in hot liquid. The goal is to wake up flavors that have gone dormant in drying, remove the parts that taste harsh, and make the chile soft enough to blend into a smooth paste.
The wider world of chile varieties is covered in the article on dried chiles; this article is about the steps that come after you have bought them.
Step 1: Inspect and clean
Look through the chiles. Good dried chiles are pliable and slightly flexible, with a rich color and a pleasant fruity smell. Brittle, pale, moldy or insect-damaged ones are best discarded. Wipe each chile with a damp cloth to remove dust. Washing under running water is also common, but dry them afterward if you plan to toast them.
Step 2: Remove stems, seeds and veins
Pull off the stem, slit the chile along its side and open it flat. Shake out the seeds and tear away the pale inner veins if you want a milder sauce. The seeds hold some heat but mainly contribute bitterness and grit, which is why many recipes discard them. Some traditional preparations toast and use the seeds deliberately, such as in certain dark moles, but this is a specific technique.
Dried chiles can irritate skin and eyes. Wear gloves, avoid touching your face, and wash hands and tools afterward. Capsaicin lingers on skin and cutting boards, and ordinary soap may not remove all of it at once.
Step 3: Toast briefly
Heat a dry comal griddle or heavy skillet over medium-low heat. Press the opened chiles flat for a few seconds on each side, until they release fragrance and may puff slightly or change color a little. Move them constantly. This usually takes under a minute in total for most thin-skinned chiles.
The central warning is simple: do not burn them. A chile that has blackened or smells acrid will make the sauce bitter, and the bitterness does not cook out. If a chile scorches, discard it and begin with a fresh one. Thicker chiles such as ancho tolerate a little more heat than delicate ones such as guajillo, but all are easy to overdo.
Toasting also produces fumes that can make people cough, because the capsaicin becomes airborne. Open a window and turn on a fan, and keep others out of the immediate area.
Not every recipe calls for toasting. Some cooks prefer to soak chiles without toasting for a milder, fruitier sauce. Others fry them briefly in a little oil. Both are accepted techniques, and the choice depends on the dish.
Step 4: Rehydrate
Place the toasted chiles in a bowl and cover them with hot, not boiling, water, or sometimes hot broth. Press them down with a plate so they stay submerged. Let them soak for roughly 15 to 30 minutes, until they are completely soft and supple. Thicker chiles may need longer.
Some cooks simmer them briefly instead, but boiling for a long time can draw out bitterness and wash away flavor. Gentle soaking is the safer approach.
Step 5: To keep or discard the soaking liquid
The liquid left after soaking will be colored and flavored by the chiles. Some recipes use a little of it to help the blender work; others recommend discarding it because it may taste bitter, especially if the chiles were toasted hard or the seeds were left in. A reasonable approach is to taste it. If it is pleasant, use a small amount; if it is harsh, use fresh water or broth.
Step 6: Blend and strain
Drain the chiles and blend them with the rest of the sauce ingredients, adding liquid a little at a time. A blender is common today, while a metate grinder or molcajete mortar was the traditional tool. For a very smooth sauce, many cooks pass the purée through a fine sieve, pressing with a spoon to leave the tough skin pieces behind. This step makes a notable difference to the texture of a mole or adobo.
After blending, many sauces are fried in a little hot fat. Chile paste splatters, so use a deep pan, a long spoon and stand back when it first goes in. The frying step deepens color and flavor.
Common mistakes
- Burning the chiles during toasting, leading to bitterness.
- Soaking in boiling water for too long, which can make the flavor flat or bitter.
- Leaving in all the seeds and veins and ending up with a gritty, harsh sauce.
- Skipping the strain when a silky texture is wanted.
- Not tasting the soaking liquid before using it.
- Forgetting gloves and rubbing eyes afterward.
Storing prepared chiles
Dried chiles keep best in a cool, dry, dark place in a sealed container. Rehydrated chiles or finished purées can be refrigerated for a few days or frozen, though the exact time depends on the recipe. Discard anything with off smells or mold.
Putting it to use
The same preparation applies to many dishes: moles such as those described in the article on mole sauce, adobo and recado pastes, and red enchilada sauces. Once you understand the sequence of cleaning, toasting briefly, soaking gently and blending, you can adjust it to a variety of chiles and dishes, always trusting your nose and your taste more than the clock.