• For the herbed yogurt: In a small bowl, whisk the yogurt, cilantro, lime zest and 1 tsp. lime juice. Reserve the remaining lime juice for the soup.
• For the soup: In a small bowl, stir the ground cumin, ground coriander, turmeric, ground ginger, and paprika. Set aside.
• In a medium (4- to 5-quart) Dutch oven or other wide soup pot, heat the olive oil over medium heat. When the oil is hot, add the onions and 1/2 teaspoon kosher salt and stir. Cover and cook, stirring occasionally, until the onion is translucent and softened, 6 to 8 minutes. Uncover and cook, stirring frequently, until the onion is well browned, another 5 to 8 minutes. Add the garlic and fresh ginger, and stir until fragrant and well combined, about 1 minute.
• Add the spice mixture and 1 teaspoon kosher salt and stir well. Add the pumpkin and stir well. Add the broth and 3 cups water. Stir and whisk to combine. Bring to a boil, reduce to a gentle simmer and cook, uncovered, for 12 to 14 minutes. Remove from the heat and let the soup cool for 15 to 25 minutes.
• Purée the soup in three batches, of coconut milk and a little (up to 1 teaspoon) lime juice to each batch as you blend. Be sure not to fill the blender jar more than two-thirds full—a little more than half is even better. Cover the blender lid partially with a folded dishtowel (leaving a vent opening uncovered to let steam out) to prevent hot soup from splashing on you. Combine the batches in a mixing bowl; rinse out the soup pot, and return the soup to the pot. Alternatively, purée the soup with the coconut milk and 2 teaspoons lime juice in the pot using an immersion blender. Taste the soup—you may need to season with more salt, and you might want to add any remaining lime juice if you like.

Tip: Indian spices are such a great match with pumpkin; be sure to “bloom” them by adding them to the aromatics and olive oil before everything else goes in.