In a large pot, heat the olive oil over medium heat. Add the chopped onion and sauté until translucent, about 3-4 minutes
Add the sliced mushrooms to the pot.
Stir in the chopped, fresh basil and white beans.
Season the mixture with salt and dried oregano. Pour in the coconut milk and water, and bring the mixture to a boil. Reduce the heat and let it simmer for about 10-15 minutes, allowing the flavors to meld and the soup to thicken slightly.
Add the garlic cloves to the pot.
Use an immersion blender to blend the soup until smooth and creamy. If you prefer a chunkier soup, you can blend only half of the mixture and leave the rest as is.
Stir in the chopped sundried tomatoes.
Taste the soup and adjust the seasoning with more salt and freshly ground black pepper if needed. Stir in more chopped fresh basil leaves, allowing the soup to simmer for an additional minute.