04Meanwhile, heat butter in a kettle and add onions and garlic. Cook, stirring often without browning, about 5 minutes. Add pumpkin cubes, shrimp broth and chicken broth and cook 20 minutes. Put the mixture through a food mill. You might use a food processsor or electric blender, but the puree will be a bit fibrous. There should be about 10 cups.05Return the soup to the kettle and add milk and cream. Simmer 5 minutes. Add shrimp, salt and pepper to taste and simmer 1 minute. Stir in coriander and serve hot.