Prep the squash: Heat the oven to 425°F (220°C).
Peel the squash with a sturdy peeler, slice in half, scoop out seeds, and cut into 1-inch cubes.
Roast the vegetables: On a large baking sheet, toss squash, onion, and garlic cloves with olive oil, salt, and pepper. Spread in a single layer. Roast for 30–35 minutes, stirring once, until the squash is tender and lightly caramelized.
Warm the aromatics: In a large pot, add a drizzle of olive oil.
Stir in thyme and nutmeg over medium heat for 30 seconds to bloom the spices.
Add the roasted veg: Transfer the roasted squash, onion, and garlic to the pot. Pour in the broth and bring to a gentle simmer for 5–10 minutes so the flavors meld.
Blend until smooth: Use an immersion blender to puree the soup in the pot until silky. Or carefully transfer to a countertop blender in batches.
Return the soup to the pot if needed.
Finish the soup: Stir in coconut milk or cream. Taste and adjust with salt, pepper, and maple syrup or honey if you want a touch more sweetness. Add lemon juice to brighten.
Serve and garnish: Ladle into bowls and top with a swirl of cream, toasted pumpkin seeds, chives, or a pinch of chili flakes for heat.