Cut the peeled and cleaned pumpkin into pieces and put it in a pot. Sprinkle with sugar on top and squeeze the juice from the mandarin directly over the pieces.
Smother on low heat until the pumpkin softens. Mash the boiled pumpkin into a smooth paste. Leave it to cool a little.
Beat the eggs to foam and add them to the pumpkin. Pour in the pudding and baking powder also, stir until homogeneous.
Pour 1/4 of the mixture into a Teflon oven dish. To the rest of the mixture, add the cocoa and stir. Pour a little of the cocoa mixture over the pumpkin one in several spots to make stripes.
Bake in a moderately preheated oven about 20 min. Leave the dessert to cool and serve.