Preheat the oven to 175 °C. Cover a small, 750 ml baking tin with baking paper.
Wash the pumpkin, cut it in half, and remove the seeds with a spoon. Grate the pumpkin with a cheese grater or in the food processor. Wash the orange in hot water and grate the peel with a citrus grater.
Sieve the flour in a bowl and add the cocoa, cinnamon, cardamom, orange zest, baking powder and the grated pumpkin. Whisk the sunflower oil with the honey in a bowl and then break the eggs into it. Stir the ingredients into a smooth mixture and then stir in the flour. Carefully stir the oil, honey and eggs into the remaining ingredients until you have a fluffy batter.
Pour the batter into the baking tin (or cake pan) and bake the cake for 30-35 minutes or until the middle of the cake starts to burst open and a wooden skewer inserted into the centre comes out clean.
Serving tip Serve the cake with Turkish yoghurt and honey or with a glaze of cream cheese and lemon.