You will also need:
Almond paste (recipe in the first post) and thick jam, e.g. strawberry or raspberry OR egg custard
Spread the jam down the centre of the strip of dough and spread or pipe the almond paste on top. Fold the sides into the centre so they overlap slightly and press together. Gently transfer to a greased cookie sheet. Brush with beaten egg, milk or water, sprinkle the pearl sugar and flaked almonds on too, and bake. This is called an old-fashioned Danish in Iceland.
If you prefer custard to jam, you spread the custard down the centre of the dough strip instead of jam and leave out the almond paste. Brush with beaten egg, milk or water and sprinkle the pearl sugar and flaked almonds on top.
Arrange on a cookie sheet, about 5 cm apart. Let rise at room temperature for 10-15 minutes, then bake at high temperature (225°C) until a light golden colour (should take about 12-15 minutes). Let it cool and then pipe icing in a zig-zag pattern over the pastry and allow to set before serving.