Start by peeling and cubing the butternut squash.
Peel the onion and quarter it.
Peel the garlic cloves.
In a slow cooker, add the olive oil.
Add the quartered onion, garlic, vegetable broth, coconut milk, ground cumin, ground coriander, ground turmeric, salt, and black pepper to the slow cooker. Stir until all the ingredients are well combined.
Cook in the slow cooker for 5-6 hours on low or 3-4 hours on high, until the butternut squash is tender.
Once cooked, use an immersion blender to blend everything until the mixture becomes smooth and creamy.
Taste and adjust seasoning if needed.
Serve the creamy butternut squash soup hot, and you can garnish it with a drizzle of coconut milk or a sprinkle of ground black pepper.