Foraging Guide: Porcini Mushroom
August 31, 2023Known as the porcini in Italy, the cep in France, the Penny Bun in the UK, the King Bolete in America and 'Die Steinpilze' in Germany, the Boletus edulis mushroom is highly prized in every country. With its deep, smoky, umami flavour when dried, foragers value these fungi so much that they often keep their whereabouts a closely guarded secret. If you’re on the look-out for them, here are a few tips to narrow down your search for this highly sought-after mushroom.
Identification
First and foremost, it is important to be able to correctly identify this mushroom. Fortunately, as long as you follow some simple rules, it has no truly poisonous lookalikes in the UK. At worst you may pop a rather bitter tasting mushroom in your basket which won’t kill you, though it will spoil your dinner.
The ‘penny bun’ is so named as its tan-brown cap resembles a freshly cooked bread roll. Rather than having gills like a field mushroom (the kind of mushrooms you find in the supermarket), it is a polypore, meaning it has tubelike structures or many pores underneath the cap, a little bit like a sponge. The pores consist of hundreds of tiny, circular to hexagonal holes housing thousands of microscopic reproductive spores. The colour of these spongy pores is off-white to pale grey in a young mushroom and can become more olive or even yellow in older specimens. The stem (or stipe) is a little bulbous, often described as club-shaped and whitish brown in colour. Towards the cap, the stem has a mesh-like pattern, or crosshatching. This will be white on a darker background, unlike the bitter bolete which has a dark pattern. The flesh should be white all the way through when cut, and importantly it should not stain blue. Also check there is no red colour to the mushroom – this can indicate that you have found the vomit-inducing devil’s bolete rather than the delicious penny bun.
There are edible mushrooms which will stain blue when cut and have red colouring but for beginners, sticking by the ‘no red and no blue’ rule will eliminate any chance of you poisoning yourself. Once you have gone through all these rules, try a very small piece of the mushroom. If it tastes good and not at all bitter, then you have a tasty cep and you can pop it in your foraging basket.
When and where to pick it
Mushrooms are just the fruiting body or the reproductive part of a much larger organism. This organism comprises many thread-like filaments called mycelium. These form associations with the roots of certain trees, a mutually beneficial relationship in which the fungi receives glucose from the tree (which it can’t make itself). In return, it sends various minerals from a much further distance than the tree roots could reach by themselves. This symbiotic connection of mushroom to tree root is called a mycorrhizal association.
They are not too fussy where they grow and can be found under conifer trees including pine and spruce as well as deciduous trees such as chestnut, beech and oak. However, they rarely, if at all, form associations with trees in the acer family, such as sycamore, field maple or ash. They are generally a summer mushroom but do need some humidity, so can pop up anytime from July to October provided there has been enough rainfall.
Preparation
Ceps do not need to be thoroughly cooked like many other mushrooms, but they do taste much better dehydrated and then reconstituted in warm water. When prepared like this they can be used in soups, risotto or pasta dishes. If eaten fresh, they can be used as they do in Italy – on top of a pizza or fried in butter and garlic and added to pasta dishes.
Mushroom Soup
Ingredients
- 1 x onion
- ½ leek
- 200g of mixed mushrooms (or 150g fresh and 20g dried mushrooms)
- 1 stick of celery
- 1 x carrot, diced
- 3 cloves of garlic
- A good slug or two of liquid aminos
- 3 tsp nutritional yeast flakes
- Approx 1 litre mushroom stock (or water and a stock cube)
- Splash of cooking oil
- Salt to taste
Method
- If using dried mushrooms, soak them for around half an hour before you start cooking.
- Chop all the veg and sweat down the leek, onion, and the stick of celery.
- Add the fresh mushrooms and throw in some crushed garlic. Fry gently.
- Once these vegetables have softened, pour in the stock, along with your soaked mushrooms, if using.
- Add the carrot and simmer for 6-7 minutes.
- Once the carrot is cooked, add the yeast flakes and liquid aminos.
- Simmer until cooked.
- Serve with fresh bread and butter.