Grease a bundt pan and sprinkle with flour or breadcrumbs. Chop the chocolates into small pieces. Beat the butter until foamy, then gradually stir in the sugar and vanilla sugar (or vanilla baking). Mix in the eggs one by one. Add the quark and mix everything to a smooth mass.
Mix the flour with the custard powder and baking powder and stir into the dough alternately with the cream and orange juice. Finally fold in the praline pieces well. If the dough still seems too firm, add a little orange juice.
Pour the dough into the mold and smooth it out. Bake at 180 ° C top / bottom heat or 160 ° C convection for approx. 45 - 55 minutes. Let cool briefly in the tin, then turn out and dust with powdered sugar. Either enjoy it immediately or wrap it in foil overnight.