Grease a baking tray (30 x 39 cm) well and dust with flour. Beat the egg white with the whisk of the hand mixer until stiff. Gradually add sugar and salt while continuing to beat. Keep beating until the sugar is completely dissolved. Fold the grated coconut and 50 g chocolate rasp into the meringue. Spread the mixture on the baking tray and sprinkle with flaked almonds.
Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 25 minutes. Remove the baking tray from the oven and immediately sprinkle with remaining chocolate shavings. Leave to cool and cut into lozenges while still warm. Allow to cool completely, then remove from baking tray. Dust with icing sugar as desired