Heat olive oil in a large pot over medium heat. Add the chopped onion and cook for 4–5 minutes until softened.
Stir in the garlic and curry powder. Cook for about 1 minute until fragrant.
Add diced butternut squash and salt. Stir to coat the squash with the spices.
Pour in the vegetable broth and bring to a simmer. Cover and cook for 15–20 minutes, or until the squash is very tender.
Stir in 1/2 cup of the coconut milk for a creamy texture.
Use an immersion blender (or carefully transfer to a blender) and blend until smooth.
Add salt and pepper per taste and serve warm. The additional coconut milk can be added before serving.