Spanisch Brötli (Baden Hazelnut Puff Pastries)

Instructions

1. Heat the oven to 425 F (220 C). Spread the hazelnuts on a baking sheet and toast 8 minutes until the skins crack and the nuts smell nutty. Rub in a clean towel to remove most of the skins, cool, then grind finely.
2. Mix the ground hazelnuts with the sieved jam into a thick paste.
3. Unroll the pastry and cut it into six 9-cm (3.5-inch) squares. Chill on a tray 10 minutes.
4. Spread the filling over one half of each square, leaving a 1 cm border. Brush the border with water, fold the other half over and press the edges to seal.
5. Cover the parcels with a plate and chill 30 minutes. This keeps the butter firm and the layers distinct.
6. Cut a deep cross in the top of each parcel down to the filling. Brush with the egg-yolk mixture and bake on a parchment-lined sheet 12 to 14 minutes until puffed and deep golden.
7. Cool on a rack and dust with powdered sugar.