Cut the pumpkin into slices, peel and remove the seeds; cook in a steamer until it is soft, about 20 minutes. Mash the pumpkin with a fork or pass it through a sieve. You will need about 125g.
Preheat oven to 180 C / Gas 4. Line a 12-hole muffin tin with paper cases.
In a medium bowl combine flour, baking powder, bicarbonate of soda, cinnamon, ginger, nutmeg, cloves and salt.
In a large bowl mix the sugar, olive oil, water and egg. Add the pumpkin puree and mix well. Add the dry ingredients and stir briefly.
Spoon the muffin mixture into the paper cases, about 2/3 full.
Bake in preheated oven for about 30 minutes. After the first 25 minutes, check muffins by inserting a skewer in the centre of a muffin, when cooked it will come out clean.
Remove muffin tin from the oven and let sit on a wire rack for ten minutes. When they are cool enough to be handled, transfer the muffins onto the wire rack and let cool completely.