Whisk the flour, salt, sugar, and baking powder in a large bowl.
Incorporate the eggs, milk, and melted butter into a well in the dry ingredients.
Combine the filling butter, cocoa, and sugar in a bowl over simmering water.
Stir in the vanilla and milk, heating for 15 minutes until thickened.
Add beaten egg yolks and cook for 10 minutes until creamy.
Mix in chopped nuts and allow the mixture to cool completely.
Whip the cream to soft peaks and fold into the cooled hazelnut mixture.
Blend raspberries with sugar and brandy, then sieve to remove seeds.
Fry ladles of batter in a buttered pan for 2 minutes per side until golden.
Roll filling into pancakes, top with coulis, and dust with icing sugar.