In a food processor, combine all the laksa paste ingredients. Blend until you have a smooth paste.
Heat the vegetable oil in a large pot over medium heat. Add the laksa paste and cook for about 5 minutes, stirring frequently, until it becomes fragrant and the oil starts to separate from the paste.
Stir in the pumpkin puree and cook for another 2-3 minutes. Then, pour in the coconut milk and vegetable broth. Bring the mixture to a simmer. Add brown sugar and soy sauce to the soup. Taste and adjust the seasoning with salt, pepper, and more sugar or soy sauce if needed. Simmer for about 15-20 minutes.
To serve, divide the cooked noodles among serving bowls. Ladle the hot laksa soup over the noodles. Top each bowl with 2 prawns, an egg, bean sprouts, green onions and a lime wedge.
