Sort the blueberries, rinse and drain if necessary. Bring to the boil with the jam and simmer for about 3 minutes.
For the waffles, whisk orange zest, 125 g butter, 50 g sugar, vanilla sugar and 1 pinch of salt until creamy. Stir in 3 eggs one after the other. Mix flour and baking powder, alternating with milk and cream.
Preheat and grease the waffle iron. Place approx. 1 1⁄2 tbsp. of dough in the middle of each waffle iron and bake until golden yellow. Bake 7 more waffles from the remaining dough and keep warm.
For the chaudeau sauce, mix 1 egg, egg yolk, 50 g sugar, wine and lemon juice in a metal bowl. Place the bowl in a hot water bath (but do not boil!) and whisk with a whisk for about 10 minutes until the cream is at least twice as thick.
Finally stir in 1 pinch of ground vanilla.
Serve the waffles, berries and chaudeau sauce immediately.