Wash the zucchini, dry and grate unpeeled with the Schnitzelwerk of the food processor or with a hand grater and set aside.
Preheat the oven to 180 ° C.
Mix the eggs with sugar, salt and vanilla sugar until frothy and stir in the soft margarine spoon by spoon. Keep stirring until a creamy foam mixture has formed.
Now mix all the other dry ingredients and stir alternately with the courgette grated into the foam, finally add 1 tablespoon creme fraiche or sour cream loosely. Pour the dough into a greased Gugelhupf tin sprinkled with hazelnuts and bake at 180 ° C for about 1 hour.
Let rest in the switched off oven for another 10-15 minutes. Let the mold cool for 10 minutes on a cake rack lined with a damp kitchen towel, then turn it out.
When the cake has cooled down, melt the chocolate fat glaze in a double boiler or in the microwave, cover the cake with it and decorate it with chopped pistachios and chocolate zebra rolls.