Step 1

In a large saucepan over medium-high heat, melt butter until foaming. Add mushrooms and cook until they have released most of their liquid, about 5 to 7 minutes.

Step 2

Stir in chicken broth, onion powder, and garlic powder and bring to a simmer. In a small bowl, whisk together milk and flour.

Step 3

Stir in milk mixture and cook until soup has thickened, about 1 minute. Season to taste with salt and pepper.