Gather your ingredients and heat a heavy-bottomed pot over medium heat. Add olive oil and butter, letting the butter melt and bubble.
Add the bite-sized chicken pieces to the pot, cooking until they turn lightly golden and are cooked through, about 5-7 minutes. Remove the chicken from the pot and set aside.
In the same pot, add sliced mushrooms and cook on medium-high heat, stirring frequently, until they release their juices and turn a deep brown, about 8 minutes. The mushrooms should smell earthy and look deeply browned and slightly crispy around the edges.
Add the minced garlic to the mushrooms and cook for about 30 seconds until fragrant, stirring constantly to prevent burning.
Pour in the chicken broth, scraping up any browned bits from the bottom of the pot, and bring the mixture to a gentle simmer. This helps meld the flavors and warms the broth.
Return the cooked chicken to the pot, stirring to combine. Let everything simmer together for about 10 minutes, allowing the flavors to meld and the chicken to absorb the broth.
Gradually pour in the heavy cream, stirring constantly to prevent curdling. Continue simmering until the soup thickens slightly and becomes velvety, about 5 minutes.
Season the soup with dried thyme, salt, and pepper to taste, stirring well. Allow it to rest for a few minutes to let the flavors develop further.
Ladle the hot soup into bowls, garnishing with fresh herbs or a drizzle of cream if desired. Serve immediately for the best velvety texture and rich aroma.
