Preheat an oven to 150°C/gas mark 2
Place the ground almonds, sugar and bicarbonate of soda in a bowl and mix together
Stir in the egg whites, vanilla essence and Amaretto, mixing until you have a thick paste
Transfer the mixture to a piping bag, then snip a 1.5cm hole at the end
Pipe even blobs, around 2.5cm in diameter, onto a baking tray lined with greaseproof paper
Using a damp pastry brush, dab each blob to get a smooth top, then dust with icing sugar
Bake for 20–25 minutes, or until the biscuits are cracked and pale gold
Leave to cool a little then dust with more icing sugar
