Preheat oven to 400 F. Place squash and onions on baking sheet and drizzle with 1 tablespoon of oil. Place in oven and roast for 30 minutes or until tender.
In large soup pot, heat 2 tablespoons of olive oil on medium heat. Saute ginger and garlic for 2 minutes. Add cumin and Thai red curry paste and saute for an additional 1 minute.
Add broth, coconut milk, lemongrass, roasted squash and onion; simmering for 5 minutes on medium heat.
Remove from heat and remove lemongrass. Let cool slightly.
Blend in batches in your blender until smooth and creamy.
Return to heat and add salt and lime juice; blending until heated through.
Drizzle remaining coconut milk on top of each bowl and garnish with chopped cilantro and chili pepper.