A rich and creamy soup that doesn't mask the earthy flavor of a wild mushroom blend. Gluten-free, low-carb, and ketogenic diet friendly.
Prepared mushrooms make this recipe way easier. The downside? They limit the quantity of trimmings necessary for the stock and come in package sizes that do not easily add up to one pound. I still use the prepared versions. The Cremini mushrooms, typically in an eight- or ten-ounce container, will require stem removal, which is used for the stock. Portobello slices are typically a 6 ounce container and will require a small amount of trimming, added to your stock. Shiitake typically is used whole, but also tends to come in a five-ounce container. Overall, the three will be about equal in the final soup and just under a pound of whole, chunky mushroom bites. If you purchase the pre-mixed “wild mushroom blend”, usually a 5-ounce container, buy four; three packages for the soup and one for the stock, as there will not be any natural trimmings.
Dried porcini mushrooms add a lovely umami quality to soups, stews, and braises, but in my view, the texture of the rehydrated mushroom is less than desirable. They are perfect for the mushroom stock made in this recipe. But first, you must rehydrate. Place the entire contents of the container in a bowl with two cups of warm water for about 15 minutes while you prep the rest of the ingredients. When they are done rehydrating, you will add the mushrooms to the stems and trimmings for the stock, and the “mushroom water” will form part of the stock base. I like the D’Artaganan brand, available in gourmet grocery stores or online.
Prepare the mushrooms as needed depending on whether you purchased packaged or loose mushrooms. For packaged mushrooms, you may still need to remove some stems (see ingredient notes). Place those stems in a separate bowl for use in the stock. For loose mushrooms, clean them by wiping them with a dry paper towel. Remove the stems, coarsely chop them and set them aside for the stock. Chop all caps and remaining mushroom parts into bite size pieces for the soup and set aside.
Start the stock by heating 1 tablespoon olive oil and 1 tablespoon butter in a large pot. Add the chopped mushroom stems, the rehydrated porcini mushrooms, the onion, the sprig of thyme (whole), 1 teaspoon of salt, and 1/2 teaspoon fresh ground black pepper. Cook on medium-low heat for 8-10 minutes until the vegetables are soft.
While the stock is reducing, heat the remaining 4 ounces (eight tablespoons) of butter in a large soup pot (your pretty one). Add the leeks. Cook on low heat for 15-20 minutes, or until the leeks just begin to slightly brown at the edges. Add the chopped mushrooms and cook for 10-15 minutes or until they are browned and tender. Resist the temptation to stir the mushrooms so that a fond develops.
Add the white wine and stir for one minute, scraping the bottom of the pan. Add the stock and cream cheese and stir to combine. Whisk if necessary to break up larger lumps. Bring to a boil for 1-2 minutes, then lower the heat to medium and simmer for 15 minutes uncovered.
Remove the soup from heat. In a separate bowl, combine the heavy cream and egg yolks and whisk to thicken a bit. When the soup is cool enough, fold it into the soup until just combined.
As an optional garnish, combine oil, parsley, salt and pepper in a mason jar (or use a hand blender) to make a parsley oil. Drizzle on top of the soup just before serving. Or simply drizzle the oil and sprinkle the salt, pepper and parsley leaves on top just prior to serving.