How to Prepare Dried Chilies for Thai Cooking: Soaking and Cooking

To prepare dried chilies for Thai cooking, first wipe them clean and snip off the stems. If you want less heat, shake out the seeds. Then choose a method based on the dish. Soak large dried chilies in hot water for about 10 to 20 minutes until soft enough to pound into curry paste. For crunch and a smoky flavor, toast or fry small dried chilies whole in a dry pan or in oil. Grind toasted chilies into flakes for dipping sauces and salads. Each method gives the same chili a different character, from soft and fruity to crisp and smoky.

What Are Dried Thai Chilies?

Dried Thai chilies are fresh red chilies that have been dried until they are shriveled, leathery or brittle. In a Thai market they look like heaps of deep crimson to brick-red pods. Their skins are glossy or slightly dull, and the seeds rattle inside when you shake a bag. Drying concentrates their flavor and adds a toasty, raisin-like depth that fresh chilies do not have.

Thai kitchens mainly use two kinds:

Large dried chilies (prik haeng met yai, often from the spur chili). These are long, slender and finger-length, with wrinkled, dark red skin. Their heat is moderate and their flavor fruity. They are the backbone of many red curry pastes and give curries their rich red color.
Small dried bird's eye chilies (prik kee noo haeng). These are tiny, pointed pods about the length of a fingernail to a thumb joint. They are bright red, thin-skinned and very hot. They are usually fried or toasted whole, or ground into chili flakes.

Type	How to recognize it	Heat	Main preparation	Typical uses
Large dried chilies	Long and slender, deep red, wrinkled, fairly thick skin	Mild to medium	Seeded and soaked, then pounded or blended	Red curry paste, panang and massaman pastes, chili jam
Small dried bird's eye chilies	Tiny, pointed, bright red, papery skin	Very hot	Toasted or fried whole, or ground into flakes	Stir-fries, toasted chili flakes, dipping sauces, larb

How to Prepare Dried Chilies for Cooking

Preparing dried chilies for cooking comes down to three decisions: whether to keep the stems and seeds, whether to soak, and whether to toast or fry. The basic cleaning steps are the same for every method.

Check the chilies. Good dried chilies are evenly colored and slightly flexible or crisp, and they smell fruity and toasty. Avoid pods with pale patches, dust, holes or a musty smell.
Wipe or rinse them. Dried chilies are often dried outdoors and can carry dust. Wipe each chili with a dry cloth, or rinse quickly and pat dry. Rinse only if you plan to soak them, because toasting and frying need dry chilies.
Remove the stems. Snip off the green or brown cap with kitchen scissors, or twist it off by hand.
Decide about the seeds. The seeds and the pale inner ribs hold much of the heat. Seeds can also feel gritty in a smooth paste. For milder results, cut the large chilies lengthwise and shake or scrape the seeds out. Small bird's eye chilies are usually left whole.
Cut or tear if needed. Snip large chilies into short pieces of about 1 to 2 cm. They soften faster and break down more easily in a mortar or blender.

Handling tip: chili oils cling to the fingers. Wear thin gloves or wash your hands well with soap. Keep your hands away from your eyes until you have.

How to Soak Dried Chilies

Soaking dried chilies, or rehydration, means covering them in water until they turn soft and pliable. This is the standard preparation for chilies that will be pounded or blended into a paste. Brittle, dry pieces will not break down into a smooth mass.

Prepare the chilies. Stem, seed and cut the chilies as described above.
Place them in a heatproof bowl. Choose a bowl large enough for the chilies to float freely.
Cover with water. Pour hot (just-boiled) water over them for the fastest result, or use warm or room-temperature water if you have more time.
Keep them submerged. Dried chilies float. Press them down with a small plate or saucer so every part softens evenly.
Test the texture. The chilies are ready when they bend without cracking, feel soft like a thick piece of leather, and have a deeper, glossier red color.
Drain and squeeze. Lift the chilies out and gently squeeze out excess water. Too much water makes curry paste wet and harder to pound.

How Long to Soak Dried Chilies

Dried chilies usually need about 10 to 20 minutes in hot water to soften. The exact time depends on water temperature, chili size and how dry the chilies are. Treat these ranges as a starting point and always check the texture.

Water temperature	Small or cut-up chilies	Large whole chilies	Notes
Hot, just-boiled water	About 5 to 10 minutes	About 15 to 20 minutes	Fastest. Best for a quick curry paste.
Warm tap water	About 15 to 20 minutes	About 20 to 30 minutes	A gentle middle option.
Room-temperature water	About 20 to 30 minutes	About 30 minutes to 1 hour or more	Slower, but some cooks find the flavor gentler.

Very old, brittle chilies may need longer. Watch for over-soaking. Chilies left in water for many hours can turn limp and lose some aroma.

What to Do with the Soaking Liquid

The soaking liquid from dried chilies is often discarded in Thai cooking. It can taste bitter or dusty and carries any grit the chilies held. Some cooks add a spoonful of it to help a blender turn the paste. If you do this, taste the liquid first and use it only if it is pleasant. Plain water is a safe alternative.

How to Cook Dried Chilies Without Soaking

Dried chilies can also be cooked straight from dry, by toasting or frying. These methods are used when the chilies should be crisp, smoky or fragrant rather than soft. Toasting and frying change the chili's flavor from fruity to nutty, roasted and deeper.

Dry-Toasting Dried Chilies

Dry-toasting means heating dried chilies in a pan with no oil until they darken slightly and smell smoky.

Heat a dry wok or heavy frying pan over low to medium heat.
Add whole or stemmed chilies in a single layer.
Stir constantly, pressing them lightly against the pan, for about 1 to 3 minutes.
Stop when the chilies turn a deeper red, puff slightly and smell toasty. Remove them from the pan right away.

Toasted chilies burn quickly. Black spots and a sharp, acrid smell mean they have gone too far and will taste bitter. Toasting releases strong chili fumes, so open a window or turn on the kitchen fan.

Frying Dried Chilies in Oil

Frying dried chilies in oil makes them crisp and glossy. It also flavors the oil itself with color and heat. Whole fried chilies are a familiar sight in Thai cashew chicken (gai pad med mamuang), where they add crunch and a smoky note. Fried chilies are also the base of Thai chili jam (nam prik pao).

Heat a few tablespoons of neutral oil in a wok over medium-low heat.
Add dry, whole chilies. Wet chilies will spatter.
Stir for about 30 seconds to 1 minute, until they darken slightly and turn crisp.
Lift them out and drain on paper. Use the red-tinted oil for the stir-fry.

Making Toasted Chili Flakes

Thai toasted chili flakes (prik pon) are made by dry-toasting small dried chilies and then grinding them. Pound them in a mortar or pulse them briefly in a spice grinder until they become coarse, rusty-red flakes. These flakes go into Isaan salads such as larb, into dipping sauces, and onto noodle-shop tables for diners to add themselves. They taste smokier and more rounded than untoasted chili flakes.

Which Method Suits Which Thai Dish?

The best way to prepare dried chilies depends on the texture and flavor the dish needs.

Method	Result	Familiar Thai examples
Soaking	Soft, fruity, easy to pound or blend	Red curry paste, panang curry paste, massaman curry paste
Dry-toasting and grinding	Smoky, coarse flakes	Larb, nam tok, dipping sauces, noodle-soup seasoning
Frying whole in oil	Crisp pods plus chili-flavored oil	Cashew chicken stir-fry, nam prik pao (chili jam)
Adding whole to simmering liquid	Gentle heat and aroma in the broth	Some soups and braises, where the chilies are not eaten

Using Soaked Chilies in Curry Paste

In curry paste, soaked dried chilies are pounded first, often with a pinch of salt that acts as an abrasive. Harder aromatics such as lemongrass, galangal and garlic are usually added next. A granite mortar and pestle is the traditional tool. Its heavy weight crushes the chili skins into a fine paste and releases their oils. A blender is faster, but it may need a little liquid and gives a slightly less fragrant result.

Substitutes for Dried Thai Chilies and Their Limitations

Several other dried chilies can stand in for Thai ones, but each changes the flavor, color or heat.

Dried chiles de árbol look similar to dried bird's eye chilies and are also hot and thin-skinned. They work for frying and flakes, but their flavor is slightly different.
Mild, large dried chilies such as guajillo can replace large Thai dried chilies in curry paste for color. They are usually milder and more earthy, and their skins can be tougher, so soak them a little longer.
Store-bought crushed red pepper flakes can replace toasted Thai chili flakes in a pinch. They are not toasted, though, and often contain many seeds, so they taste sharper and less smoky. Briefly toasting them in a dry pan helps.
Fresh red chilies give heat but not the deep, dried-fruit flavor. Curry pastes made with them taste brighter and look less deeply red.

Common Mistakes When Preparing Dried Chilies

Most problems with dried chilies come from burning, under-soaking or keeping more seeds than intended.

Burning while toasting: use low to medium heat, stir constantly and remove the chilies as soon as they smell toasty.
Under-soaking for paste: chilies that still crack when bent will leave hard flecks in curry paste.
Frying wet chilies: dry the chilies well after rinsing to avoid spattering oil.
Too much heat: remove the seeds and inner ribs, or use more large chilies and fewer bird's eye chilies.
Breathing in fumes: toast and fry with good ventilation, and keep your face away from the pan.