Warm the olive oil over low heat in a large saucepan or Dutch oven.
Add minced garlic and cook for one minute, stirring occasionally.
Add the sliced mushrooms, dried thyme, onion powder, salt, and pepper and cook over medium heat. Cook until mushrooms have softened and reduced, stirring occasionally, about 5 minutes.
Stir in the apple cider vinegar, followed by the vegetable broth and coconut milk.
Sprinkle the rice flour a little at a time (don't dump) over the mixture and stir until dissolved. Bring mixture to a boil and then reduce heat to low, cover, and simmer for 20 minutes.
Use an immersion blender and puree half of the soup. If you don't want any full mushroom slices remaining, blend soup until smooth. Don't have an immersion blender? Carefully blend hot soup in batches in a high speed blender, ensuring lid is secured.
Season with additional salt and pepper, if desired. Serve warm.
*Store soup in an airtight container in the refrigerator for up to 5 or 6 days. Soup can be kept in the freezer for up to 2 months.
Notes
*The soup will thicken a bit more once chilled. Feel free to thin it to desired texture with extra coconut milk or vegetable broth. Quick Tips
Buy sliced mushrooms to cut down on prep time
Use prepared minced garlic instead of mincing your own