I love, really love, mushrooms … raw, cooked, on pizza, in salads, definitely sauteed on steak, and most especially as the featured ingredient in a rich, creamy soup. I often make a meal of the soup, with a big chuck of buttered sourdough on the side, but it’s also a lovely starter or complement to a light main course.
The key to developing the rustic flavor is to cook the mushrooms low and slow in the butter/olive oil. I personally think this is best done in a cast iron dutch oven. I use the one my Nana brought from Ireland to the United States when she immigrated to Washington State in 1946. It was her mother’s and is now over 100 years old. It is one of my most treasured galley items and infuses the secret ingredient of love into every dish.
- Get creative with your choice of mushrooms for a slightly different flavor profile. Fresh baby portobellas and criminis are more robust than the white button variety. Dried oyster, shitaki and lobster each bring a different nuance than porcinis.
- Make it vegan by replacing the butter and cream with dairy-free alternatives and use vegetable stock in lieu of chicken stock. Or skip the cream al together for a broth-based soup.
- Don’t have fresh thyme or tarragon? Substitute with 1/2 teaspoon dried thyme and 1/4 teaspoon dried tarragon. You can also leave out the herbs altogether.
- Some folks prefer their mushroom soup rustic instead of pureed. Simply skip the blender step, if so.
- 4 T salted butter
- 1 T light olive oil
- 20 oz sliced white or baby bella mushrooms
- 1 oz sliced dried porcini mushrooms (optional)
- 1/2 cup diced yellow onion
- 3 cloves garlic, diced
- 2 T white, all-purpose flour
- 3 sprigs (with multiple branches) fresh thyme (or 1/2 teaspoon dried)
- 1 sprig tarragon (or 1/4 teaspoon dried or can be omitted)
- 4 cups chicken stock (or vegetable stock)
- 1/2 teaspoon ground black pepper
- 1 cup heavy whipping cream
- Place the dried mushrooms in a small bowl and cover with 1.5 cups warm water and set aside.
- Heat the butter and olive oil over medium heat and add the sliced mushrooms. Cook until soft and giving off liquid.
- Reduce to low and cook, stirring every 10 minutes or so, until the juices are almost evaporated and the mushrooms are a deep brown. This is generally between 25 to 40 minutes; be patient!
- Pull out and set aside a few nice looking mushrooms for garnish. I save 3 per bowl.
- Drain the porcini mushrooms, reserving the liquid. Slice into half inch pieces.
- Add the onions and porcini mushrooms to the cooked mushrooms. Turn up to medium heat and cook for five minutes, until onions are soft.
- Add the garlic and cook one minute more.
- Reduce to low and slowly sprinkle the flour on top of the mushrooms, mixing well. Cook for two minutes, stirring constantly so you don’t get any flour lumps.
- Slowly add the chicken broth while stirring.
- Tie the thyme and tarragon together with kitchen string and submerge in the broth.
- Bring mixture to just boiling, turn down to low and simmer for one hour uncovered, stirring every 15 minutes.
- Remove from heat and allow to cool for 20 minutes.
- Transfer in small batches to a blender and blend or puree to your desired consistency. Add the reserved porcini mushroom liquid in 1/4 cup increments as needed. (I like to leave mine a bit chunky; some prefer it fully pureed.)
- Return soup to pot and slowly whisk in the heavy cream.
- Simmer over low heat until desired temperature.
- Ladle into bowls and garnish with reserved mushrooms, thyme leaves and finely chopped tarragon.