Mushroom Tea is made by decoction rather than infusion. A decoction is made by simmering the mushroom in water for 15 to 20 minutes. This is sometimes referred to as a hot water extraction.
Making mushroom tea is a good way to extract the flavour and nutrients from tough, woody or rubbery mushrooms like Reishi, Many-zoned Polypore, Chaga and Birch Polypore. The same piece of mushroom can be used to make several batches of tea by adding more water and decocting again. The tea can be drunk as a tea or used as a mushroom stock in cooking.
Some mushrooms have a bitter taste and you might want to add other ingredients to suit your taste. Here is a recipe for Reishi Tea from Carl Shillingford using wild fruits to balance the flavour:
5g dried / 30g fresh reishi
6 crab apples, quartered
10 rose hips
6 to 8 fresh sage leaves
honey to taste
Chop, grate or powder the reishi and add it to the water in a saucepan. Bring to the boil and then turn down the heat and simmer for 15 mins. While the mushroom is cooking add the rose hips, the crab apples and the sage leaves. Once the tea is cooked stir in the honey to taste, strain into cups and serve.