The most common method of cooking mushrooms is to sauté them. However, boiling mushrooms is a good method to create a stock for a soup or sauce. Fresh mushrooms retain their flavour during boiling, making dried mushrooms a better choice for releasing flavour into water. Dried mushrooms release their flavour during the rehydration process.
Wash the mushrooms thoroughly. Some recipes whimsically refer to the moss or mould on the mushrooms, but as most mushrooms are grown on manure. Wash them thoroughly. Wipe every surface of the mushroom with a cloth, or use a soft brush. Don’t scrub the mushrooms so that you damage the surface.
Cut off the base of the stem. You will notice that the step splays out towards the bottom and hardens. This is the bit you need to remove.
Chop up your mushrooms according to your own preference. You may just want to separate the cap from the stem, or you may want to leave them whole. If you are preparing stuffed mushrooms, separate the cap and the stem and boil both. You can mash up the stem to form part of your filling.
Bring a pan of water to the boil. The quantity of water you use depends on the quantity of mushrooms you wish to cook and whether or not your aim is to use the mushrooms or use the liquid. If you intend to eat the boiled mushrooms, make sure there is enough water in the pan to cover the mushrooms. If you intend to use the fluid as a stock, heat 3 tbsp of butter in the pan first and then add 2 tbspn of water for about 250 grams (½ pound) of fresh mushrooms.
Use seasoning to taste. Salt will draw the flavour out of the mushrooms and into the water. If you want to eat the mushrooms, don't add salt; this will help you retain most of the flavour in the mushrooms. If you are making a sauce, add a pinch of salt for each 250 grams (½ pound) of mushrooms.
Boil the mushrooms for about 10 minutes before draining out the fluid. Drain the fluid into a container if you intend to use it as a base for a sauce.