Sauté the onions with a pinch of salt in a wok. Add the pumpkin chunks. Add just a little water for the vegetables to cook, without browning. Cover and leave to cook until the onions and pumpkin are soft. You may add lemon grass or kaffir lime leaves at this point, if required. Blend the vegetable mixture into a smooth paste, retaining the water released from the cooking, if any. Do not strain. Pour the blended mixture back into the cooking vessel to heat.
Just before serving, remove the soup from the heat and add the coconut milk. Do not allow the soup to boil once you have added the coconut milk. Pour as much milk as required, depending on the desired creaminess and thickness of the soup. Add crushed black pepper.
Garnish with parsley or roasted pumpkin seeds. Marinate the pumpkin seeds in lime juice and salt, and then bake in the oven until the seeds are crisp and toasted. Sprinkle as garnish for the soup.
This creamy soup is delicious, served either hot or at room temperature. Could also be served chilled.