Mix the flour, lemon zest, raspberry powder and salt in a bowl. Add the butter and rub together using your hands to form an even, crumbly mixture. Beat the egg white, icing sugar and vanilla paste well, add and quickly combine to form a soft dough. Shape into a roll approx. 4 cm in diameter, cover and chill for approx. 1 hr.
Combine the hazelnuts, sugar, single cream, gingerbread spices and salt. Cut the dough into 16 slices, halve each slice. Press one piece of dough into each of the prepared holes in the tart tins, pressing into the sides to cover the entire hole. Roll out the remaining pieces of dough to a thickness of approx. 4 mm and cut into strips approx. 3 mm wide. Spoon the filling into the hollows and arrange the strips of dough on top in a lattice pattern, press down the edges.
Bake each tray for approx. 10 mins. in the centre of an oven preheated to 200°C. Remove from the oven, allow to cool a little, then leave to cool completely on a rack.