Heat a heavy-bottomed pot over medium heat and add a tablespoon of oil or butter. Once shimmering, add the chicken pieces and cook until lightly browned and cooked through, about 5-7 minutes. Remove and set aside.
In the same pot, add the remaining butter and sliced mushrooms. Sauté over medium heat, stirring occasionally, until the mushrooms release their juices and turn a deep, smoky brown, about 8 minutes. The mushrooms should be deeply browned and fragrant.
Add the minced garlic to the mushrooms and cook until fragrant, about 30 seconds. The aroma of garlic should become noticeable, and the garlic should be slightly softened.
Pour in the chicken broth and bring the mixture to a gentle simmer. Use a spoon to scrape up any browned bits from the bottom of the pot, enhancing flavor.
Stir in the heavy cream gradually, pouring slowly while stirring, until the broth thickens slightly and becomes velvety. This creates a rich, smooth base for the soup.
Return the cooked chicken pieces to the pot, stirring to combine. Let everything simmer together for about 10 minutes, allowing flavors to meld and chicken to stay tender.
Season the soup with salt, pepper, and thyme to taste. Adjust seasoning as needed, then let the soup rest off heat for 5 minutes to develop full flavor.
Serve the soup hot, garnished with fresh herbs or a drizzle of cream if desired. Enjoy this cozy, velvety bowl of comfort!
