Knead flour, baking powder, 60 g sugar, salt, egg, and 125 g cold butter (cut into small pieces) with a hand mixer using the dough hook until combined. Knead by hand for 1-2 minutes until smooth shortcrust pastry forms. Wrap in foil and refrigerate for 30 minutes.
While the dough chills, preheat oven to 175°C (350°F) for electric, 150°C (300°F) for convection, or gas mark 2.
Grate 200 g raw marzipan on the coarse side of a grater into a bowl. Add 2 tablespoons brandy and 400 g ground hazelnuts. Mix well.
Melt 125 g butter in a saucepan over medium heat. Stir in 100 g crème fraîche, 250 g sugar, and 2 points vanilla sugar. Bring to a boil, stirring constantly, over medium-high heat for 1 minute.
Pour the hot butter mixture over the marzipan-nut mixture and mix thoroughly.
Grease a 35 by 40 cm baking sheet. Remove the chilled dough from foil and roll out onto the sheet. Press the dough to the edges and corners with your hands.
Spread the nut mixture evenly over the pastry.
Bake on the 2nd rack from the bottom for 20-25 minutes until the edges turn golden.
Cool on the baking sheet for 10 minutes. Cut into 16 squares roughly 8 by 8 cm each. Cut each square diagonally to make 2 triangles, creating 32 wedges total.
Roughly chop 200 g semi-sweet couverture. Melt in a hot water bath, stirring occasionally, until smooth.
Dip the tips of each nut wedge into the melted couverture. Let dry on a wire rack.