Start by cleaning the pumpkin and cutting it in half. Remove the seeds and fibrous strands by hand of using a spoon if you need to.
Carefully peel the peel off the pumpkin flesh, then add it to a saucepan with some water. Bring it to a boil, the lower the heat to a simmer and cook for about 30 minutes until the pumpkin becomes tender enough to mash with a fork.
Take off the heat and allow to cool a bit before pureeing the pumpkin in a blender.
In another large bowl mix together the maize meal (cornmeal) with a small amount of water until a paste forms.
Combine the maize meal paste with the pureed pumpkin, mixing well. You should get a thin soup-like consistency.
Mix in the peanut butter, salt and sugar and mix until well-incorporated.
Return the mixture to the pan and on a medium-high flame. Being to a boil, then turn the heat down to a simmer and cook for 10 minutes until the soup thickens.
Adjust the consistency to your preference: if it's too thick, add a little more water or add more maize meal if it's too thin.
Serve the Nhopi hot and enjoy!