For this soup, I used a mixture of shiitake, chestnut mushrooms, oyster mushrooms, porcini, white beech and eringi (king trumpet) mushrooms. These mixtures of mushrooms are often available in supermarkets. If not, use at least three different types that are easily available, such as shiitake, chestnut and oyster mushrooms.

One good idea would be to always have some dried mushroom, such as porcini, in your kitchen cupboard. This is a good way to save money but get max flavor. However, rehydrate the dried mushrooms in a little bit of salted water for at least an hour.

Working with fresh mushrooms, there are two crucial rules to follow. First, never ever wash mushrooms. They would just soak up water. The second rule is: fry the mushrooms at a very high heat (using no oil or butter). There will be a lot of sizzling and you will see the mushrooms shrink and emit water. 

Basic Method

1. Brush any visible dirt off the mushrooms, cut off the thinnest bit of the stem (often a little dried out) and halve or quarter the mushrooms. Your soup will have relatively big chunks of mushroom in them. If you prefer finer cut, that's great too!
2. Finely chop a shallot and a clove of garlic.
3. Cut a few slices of chili.
4. Tear the little leaves off a few sprigs of thyme.
5. Heat a skillet; once hot, add the mushrooms and fry until golden. Turn the heat down to medium.
6. Add a little bit of butter (or vegetable oil, if making a vegan soup) and the chopped shallot; fry for a minute.
7. Add the chopped garlic, thyme and chili and fry for another 30 seconds.
8. Add stock (best would be mushroom stock, but herbs stock is excellent too) and finely chopped parsley and let the mixture simmer for twenty minutes.
9. Add some Worcestershire sauce to taste.
10. Season to taste with pepper and salt.

Just a note on the stock: you can buy good - but often expensive - stock in supermarkets, or make it yourself, which takes a lot of time. So if you take the shortcut to stock cubes, be sure to select cubes with a relatively low sodium content; some brands contain up to 40% salt! Also, when using cubes, be very careful adding additional salt.

For a nice and luxurious finishing touch, add a little bit of cognac, either when done frying the mushrooms (the alcohol will burn off immediately) or just before serving (it won't).