01 - Set oven temperature to 425°F.
02 - Combine carrots, onion, garlic, 1 tablespoon olive oil, 1/2 teaspoon salt, and black pepper on a baking sheet. Roast for 25 to 30 minutes, turning once halfway through, until carrots are tender and caramelized.
03 - Heat remaining 1 tablespoon olive oil in a large pot over medium heat. Add ginger, ground cumin, and ground coriander; sauté for 1 to 2 minutes until aromatic.
04 - Add roasted vegetables to the pot. Pour in vegetable broth and bring to a boil. Reduce heat and simmer for 10 minutes.
05 - Stir in coconut milk, reserving 2 tablespoons for garnish if desired. Simmer an additional 5 minutes.
06 - Remove from heat and purée soup using an immersion blender or in batches with a standard blender until smooth and silky.
07 - Stir in lime juice. Adjust salt to taste.
08 - Ladle soup into bowls, drizzle reserved coconut milk on top, and garnish with fresh herbs such as cilantro if desired.