Best Creamy Mushroom Soup

Heat the butter and olive oil together in a large Dutch oven or heavy-bottomed pot over medium-high heat until the butter is melted. Add the diced onions and sauté for 2-3 minutes, until they begin to soften. Add the minced garlic and cook for about 1 minute more, stirring constantly, until fragrant.

Add the sliced mushrooms and 2 teaspoons of the fresh thyme leaves to the pot. Cook, stirring occasionally, for about 5 minutes, or until the mushrooms have released their liquid and started to brown.

Sprinkle the flour evenly over the cooked mushrooms and vegetables. Stir well to combine, coating the mushrooms. Cook for 2 minutes, stirring constantly, to cook out the raw flour taste.

Gradually pour in the chicken broth (or vegetable broth), whisking constantly to prevent lumps. Season with 1-2 teaspoons of salt and 1/2-1 teaspoon of pepper (adjust to your taste).

Bring the soup to a simmer. Reduce the heat to low-medium, cover the pot, and allow the soup to simmer gently for 10-15 minutes, stirring occasionally, until the soup has thickened slightly and the flavors have melded.

Reduce the heat to low. Stir in the heavy cream. Allow the soup to heat through gently. Do not let it boil rapidly after adding the cream.

Stir in the chopped fresh parsley (if using) and the remaining 2 teaspoons of fresh thyme leaves. Taste and adjust seasoning with more salt and pepper if needed. Serve the creamy mushroom soup hot, garnished with extra parsley or thyme if desired.