Line 3 large baking trays with baking parchment. Put the butter and caster sugar in a bowl and whisk until pale and creamy. Whisk in the egg yolk and 2.5ml (1/2 tsp) almond extract.

Sieve over the flour and Baking Powder, add the ground almonds and carefully mix together to make a mixture that resembles a crumble topping. Using your hands, bring the mixture together to form a firm dough. Turn onto a lightly floured surface and knead until smooth and pliable.

Roll out the dough to a thickness no greater than ½ cm (1/4 inch). Using a 7cm (2 ¾ inch) wide butterfly shaped cutter stamp out approx. 40 cookies, re-rolling the dough as necessary. Arrange on the prepared baking trays, prick lightly with a fork and chill for 30 minutes.

Ten minutes before baking, preheat the oven to 180°C (160°C Fan). Bake the cookies for 10-12minutes until firm and lightly golden around the edges. Leave to cool on the baking trays for 10 minutes before transferring to a wire rack to cool completely.

To ice, make up the Egg White Powder with 50ml (10tsp) warm water as directed on the packet. Sift the icing sugar into a bowl. Add the remaining Almond Extract and the blended egg white.

Carefully combine the wet and dry ingredients together to make a soft, spreadable icing – if it is too dry, add some more sifted icing sugar, 15ml (1tbsp) at a time. Beat until smooth and glossy.

Put about 30ml (2 tbsp.) of the icing in a small bowl and add a little food colouring to make a subtle pink shade.

Spoon a further 30ml (2 tbsp.) of the white icing into a small piping bag fitted with a No: 2 size plain piping nozzle. Pipe a line approx. 1mm from the edge of all the cookies, marking out the wings and body.

Working on one butterfly at a time, spoon approx. 2.5nk ( 1 ½ tsp.) of the white icing into the centre of each butterfly wing and gently spread it to fill the centre, tapping gently to make an even layer and release any air bubbles. Add a little more icing if necessary in order to achieve a smooth, well-covered surface. Flood the centre of the biscuit with a little pink icing to make the body.

Decorate the wings with sprinkles of your choice and place back on the wire rack whilst you ice the remaining cookies.

The icing will be firm enough to serve after 1 hour. For a firmer set, leave the icing to dry for 4 hours – this icing will not dry out to a crisp.