Wash and clean the pumpkin and apple. Now cut both into rough pieces and remove the seeds. Preferably grate into small pieces in a blender.
Beat the two eggs and mix them together with the birch sugar in a bowl with a hand mixer. Add the oil of choice and mix as well.
Add the flour and baking powder and mix with a hand mixer. Next, add the spices: Cinnamon, ground cloves and cardamom.
Now fold in the grated pumpkin and apple with a spoon.
Chop the walnuts into small pieces and also fold in carefully.
Grease a cake pan (about 8" (20 cm) in diameter) and pour in the batter.
Bake the cake in the oven for about 40 minutes. Then let it cool down.
For the frosting: put all the ingredients in a bowl and beat with a hand mixer until creamy. Spread on the cake and put in the fridge for about 1 hour.
After that you can toast pumpkin seeds in a pan and spread them on the cake.