Preheat the oven to 375 degrees F. 

Spread out the onion and cauliflower in a single layer on a baking sheet. Drizzle with olive oil and sprinkle with salt and pepper. 

Roast for 15-20 minutes until golden, stirring once.

Place the cauliflower and onions in a large pot and add the chicken stock.

Stir in the coriander, turmeric, cumin, and a pinch of salt.

Bring to a boil and let boil for 5 minutes.

Remove from heat.

Using an immersion blender, puree ingredients in the pot until smooth. (Alternatively, carefully transfer to a blender.)

Stir in the coconut milk and warm the soup to serve.

Taste to adjust seasonings as necessary.

Serve with roasted cashews and top with parsley.