Soak the dried porcini in 1 cup boiling water for 20 minutes. Reserve the soaking water and roughly chop the porcini mushrooms.
Place the cauliflower florets in a large pot on medium heat with 1 cup of almond milk and the reserved porcini water. Cover and allow to steam for approximately 10 minutes until the florets are very tender. Transfer everything to a blender, add in 1 cup almond milk and blend until completely smooth. Set aside.
Add the coconut oil or butter to the pot and then sauté the garlic and onion for 3 to 4 minutes. Add in the chopped mushrooms, thyme and salt and pepper and cook for 10 minutes until the mushrooms have softened.
Add the cauliflower puree, vegetable stock and chopped porcini to the pot, cover and let simmer for 20 minutes.
Using an immersion blender, blend the soup for a few seconds, or longer depending on how chunky you like your soup. Serve topped with fresh thyme.