Preheat the oven to 400F degrees.
Using a cookie cutter (or a sharp knife) cut out an even number of puff pastry pieces.
Generously spread the almond pastry filling on half of the cut-out shapes, and then use the remaining shapes to top them off. Using a fork, press together the edges of the pastry to seal in the almond filling.
Transfer the pastries to a lined baking sheet. Brush the tops with the beaten egg.
Bake for 20 minutes, until the pastries are golden brown. Set them aside to cool.
Meanwhile, whisk together the powdered sugar and milk. Add more sugar or milk to reach desired consistancy. Stir in food coloring as desired.
Drizzle the icing over the cooled pastries to decorate. Alternatively, you can brush the icing on using a pastry brush or new paint brush.