I use edible mushrooms and/but I do listen to Jefferson Airplane while making this soup. On August 17th, 1969 Jefferson Airplane played White Rabbit at Woodstock, exactly ten years before I was born. I'd say I must have some kind of soul connection to the band. They also played Plastic Fantastic Lover and Volunteers, two of my favorites. As I've mentioned before I play this song during the Drink Me/Eat Me course at One Sister Underground.
1130 g of mushrooms. This is about 3 and a half pounds of mushrooms (I think). Here's what I buy: 2 large packages of white button mushrooms. 2-4 oz. packages of mixed mushrooms-usually oyster, crimini, shiitake, and 2-4 oz. packages of maitake mushrooms.
3 carrots, chopped in stock fashion
1 fennel bulb, chopped
1 onion, chopped
1 can of tomato paste, 8 oz can.
3 garlic cloves
1T Kosher salt
2 bay leaves
5 sprigs of thyme
Place the white buttons and mixed mushrooms, all coarsely chopped, into a stock pot and sweat with carrot, fennel, onion and garlic in a touch of vegetable or canola oil. Reserve maitakes on side. Add cold water, about a gallon and a half to two gallons, bring to boil. Add salt, peppercorns, tomato paste, bay and thyme. Turn down to a heavy simmer and allow to cook for 4 hours. After about two hours, I add the 8 oz or 230g of maitake to a sheet tray, bake for about 5 minutes at 350 then add to a small stock pot and cover with about 2 quarts of water, add about a 1/2 teaspoon of kosher salt and let come to a boil then turn down and allow to simmer for 90 minutes. Taste both stocks. Make sure they have a nice mushroom flavor, adjust seasoning if needed or cook a little longer and then strain. I discard my batch with the veggies but the maitake I save and saute in butter. They taste not "so amazing" after this long water soak but I still love them. Ok, so. After both batches are strained I mix them together and then strain through cheese cloth back into a clean stock pot and reduce for one hour. After the hour is up, I check for seasoning. I usually don't have to add much, maybe a pinch of salt. Once it is nice and complex, full of mushroomy deliciousness I turn it off and let it cool. I haven't measured it at this point but I think I have about ten cups to twelve cups (closer to twelve) so once it is cool I add ten to twelve egg whites to the batch and turn back on the heat. Using a flat bottomed spatula I gently pull the egg whites to the surface as they cook and run the spatula along the sides to make sure there is no sticking because they will scorch. Once it reaches a heavy simmer and the soup is running consistently but gently through the egg raft I leave it alone for another hour. After the hour is up I turn off the soup and let the egg settle. The final straining process is run through a cheese cloth into deli containers or an airtight container where I will hold it until service. Usually, I am left with about 30 ounces give or take a few of this lovely, clarified, mushroom soup. You can freeze it, refrigerate it, use it as a base for other soups and sauces, cook down sliced shiitake in butter with Madeira, shallot, thyme, add a little of this stock, reduce, mount with butter to thicken, serve over steak or grilled tofu. You can do anything with it, drink it from teacups. Cheers.