Ingredient

Shiitake

Shiitake are one of the few ingredients where the dried version is arguably better than the fresh. Drying concentrates and transforms them, generating savoury compounds the fresh mushroom does not have — so a bag of dried shiitake in the cupboard is a more useful thing than a punnet of fresh ones in the fridge.

Why drying improves them

Fresh shiitake are pleasant — meaty, faintly smoky, mildly savoury. Dried shiitake are something else: intensely savoury, with a deep, almost bacon-like aroma.

The transformation is a real chemical one. Drying and the enzyme activity that accompanies it generate compounds that are not present, or are present in far smaller amounts, in the fresh mushroom — including guanylate, a savoury compound that is particularly effective alongside the glutamate in soy sauce, kombu, tomato or parmesan. The two together produce a savoury effect noticeably greater than either alone, which is why dashi made with kombu and dried shiitake is so much more than the sum of its parts.

The soaking water is the point. Everything that came out of the mushroom is in it. Straining it and using it as stock is not a thrifty afterthought — it is frequently more valuable than the mushrooms themselves.

Using dried shiitake

1. Rinse them briefly to get rid of grit.
2. Soak in cold water for several hours, or overnight in the fridge. Cold and slow gives a much better-flavoured liquid than hot and fast; hot water is the shortcut when you have twenty minutes rather than a night.
3. Lift the mushrooms out rather than pouring, so the grit stays at the bottom of the bowl.
4. Strain the liquid through a fine sieve or a cloth. This is your stock — use it in the dish, in a soup, in a braise, or in rice.
5. Squeeze the mushrooms out, cut off the stems, and slice the caps.
6. Keep the stems. They are too tough to eat but they are full of flavour, and they go into a stock pot.

How to use them

• In dashi, with kombu, as the vegetarian version of the Japanese base stock.
• In braises and stews — Chinese red-braised dishes, stews with soy and star anise, anything wanting depth.
• In risotto and pasta, sliced, with the soaking liquid making up part of the stock.
• Fresh, roasted or fried hard until the edges crisp. Fresh shiitake brown well and are excellent simply pan-fried with butter and soy.
• Fresh, in a stir-fry, added early enough to lose their water and start colouring.
• As a savoury booster — a couple of dried shiitake in a beef stew, a lentil soup or a tomato sauce adds depth without tasting of mushroom.
• Powdered. Blitzed dried in a grinder, shiitake powder is a seasoning that goes into rubs, sauces and dressings.

Fresh against dried

Flavour

Fresh: mild, meaty, slightly smoky. Dried: intense, deeply savoury, aromatic. Genuinely different ingredients.

Texture

Fresh: firm and springy. Rehydrated: denser, chewier, more substantial.

Best use

Fresh for frying and roasting where texture leads. Dried for anything with liquid, where the soaking water is half the benefit.

Stems

Tough in both. Remove them and keep them for stock.

Keeping

Fresh: about a week in a paper bag in the fridge. Dried: essentially indefinitely in a sealed jar.

Cost

Dried are cheaper by the amount of flavour delivered, by a wide margin.

Common questions