First preheat the oven to 175 degrees. Grease a Guglhupfform well and then flour it!
In the meantime, cream butter with sugar and vanilla sugar. Gradually add the eggs and mix until creamy. Finally, stir in flour, cornstarch and baking powder, as well as the eggnog.
Finally, pour the batter into the pan, smooth it out and bake at 175 degrees on the second rack from the bottom for about 50 minutes. Wooden stick test!
Then let it cool and dust with powdered sugar