Heat the butter in a Dutch oven over medium heat until the bubbling ceases. Add the shallots and cook for 2 minutes, then add the sliced garlic. Continue cooking until the shallots have softened and are translucent, approximately 2 more minutes.
3 tablespoons unsalted butter, 2 shallots, 4 cloves garlic
Sprinkle the flour over the onion/garlic mixture, stir, and cook for 1 minute.
4 tablespoons all-purpose flour
Stir in the sherry (with a wooden spoon) and scrape the bottom of the pan to deglaze the pan.
¼ cup dry sherry wine
Add the broth, salt, pepper, bay leaf, and thyme sprigs and bring to a boil.
6 cups low-sodium chicken broth, 1 teaspoon kosher salt, ¼ teaspoon freshly ground black pepper, 3 sprigs fresh thyme, 1 bay leaf
Add the mushrooms and bring back to a boil.
1½ pounds cremini mushrooms
Reduce the heat to low and simmer, partially covered, for 30 minutes.
After 30 minutes, use an immersion blender to purée the soup until smooth and creamy.
Add the half-and-half and reheat.
¾ cup half-and-half
If serving immediately, ladle soup into bowls and garnish with chopped fresh parsley and toasted, sliced almonds or homemade croutons.
Chopped fresh thyme leaves, Sliced sautéed mushrooms, Sliced almonds, Homemade croutons
If using as an ingredient in other recipes, remove from the heat and cool to the touch, then cover and refrigerate until ready to use.