In a pan, warm oil over medium-low heat. Sauté onion and ginger until soft, 8 minutes. Do not let brown. Add jalapeño and garlic; cook for 3 minutes, stirring often.
Stir in lime zest, pumpkin, coconut milk and broth. Bring to a boil, reduce heat to medium-low and simmer for 20 minutes, stirring occasionally. Season with salt. Remove from heat, let cool slightly, then puree in a blender. Serve hot.