01 -
In a large pot, melt the butter with the olive oil over medium heat. Add the diced onion and sauté for 3-4 minutes, until softened and translucent. Add the minced garlic and fresh thyme (or dried thyme) and cook for another 1-2 minutes until fragrant.
02 -
Add the sliced mushrooms to the pot. Cook, stirring occasionally, for 8-10 minutes, until the mushrooms release their moisture and become soft and browned. If you like, you can deglaze the pot with a splash of white wine or sherry at this point, scraping up any brown bits from the bottom of the pot for extra flavor.
03 -
If you want a thicker soup, sprinkle the flour over the mushrooms and stir well to combine. Cook for 1-2 minutes to get rid of the raw flour taste. This will help thicken the broth as it simmers.
04 -
Pour in the vegetable or chicken broth and bring the soup to a simmer. Let it cook for 10-15 minutes, allowing the flavors to develop and the soup to reduce slightly.
05 -
For a smoother soup, use an immersion blender directly in the pot to blend the soup until creamy (you can leave some chunks for texture if you prefer). Alternatively, carefully transfer the soup to a regular blender in batches, then return it to the pot.
06 -
Stir in the heavy cream (or half-and-half for a lighter version) and cook for an additional 3-5 minutes until heated through. Taste the soup and adjust the seasoning with salt and pepper as needed.
07 -
Ladle the soup into bowls and garnish with fresh parsley. Serve with a side of crusty bread or a sprinkle of grated Parmesan if desired!