Heat the oil in a large pot over medium heat. Add the onions and sauté for approximately 5 minutes, or until softened.
Add the garlic powder, onion powder, ground coriander and cumin. Cook for approximately 1 minute, stirring so the spices don't catch.
Pour in the vegetable stock and add the pumpkin. If using water instead, stir in the vegetable stock powder. The liquid should cover the pumpkin.
Bring to a gentle boil, then reduce the heat and simmer for approximately 20–25 minutes, or until the pumpkin is completely tender.
Remove from the heat and blend with a stick blender until smooth. Alternatively, carefully blend the soup in batches. If it's thicker than you'd like, add a little extra stock or water.
Return the soup to low heat. Stir through the coconut cream and peanut butter, then heat gently for approximately 5 minutes. Do not boil.
Season with salt and pepper to taste. Add chilli flakes if you'd like a little heat, then garnish with fresh coriander before serving.