Grease and crumble the gugelhupf pan.
Stir the butter / margarine until frothy.
Add sugar, vanilla sugar and salt and stir well.
Gradually add the eggs and stir.
Add the zest of half an orange. _ Squeeze out orange juice and have it ready.
Preheat the oven to 175 degrees.
Mix the flour / baking powder mixture alternately with the orange juice and the 2 tablespoons of orange liqueur into the dough.
Pour the batter into the baking pan. Bake for about 60 minutes. Let rest in the mold for 10-15 minutes. Then fall.