Preheat the oven to 400°F (200°C). Toss the cubed butternut squash with 1 tablespoon of olive oil, then spread evenly on a baking sheet. Roast for about 25-30 minutes until the edges are golden and the squash is tender.
Meanwhile, heat the remaining 1 tablespoon of olive oil in a large pot over medium heat. Add the diced onion and minced garlic, sautéing until translucent and fragrant, about 5 minutes.
Add the minced ginger to the pot and cook for another minute until it releases a spicy aroma.
Once the roasted squash is cool enough to handle, add it to the pot. Pour in the vegetable broth, bringing the mixture to a gentle simmer.
Use an immersion blender to purée the soup directly in the pot until smooth and creamy. Alternatively, carefully transfer the mixture to a blender and purée, then return it to the pot.
Stir in the coconut milk, then season with salt and pepper to taste. Continue cooking for another 5 minutes to allow flavors to meld and the soup to heat through.
Taste the soup and adjust the salt, pepper, or ginger if needed for your preferred flavor balance.
Serve the soup hot, garnished with a drizzle of coconut milk or fresh herbs if desired.
