Put the butter and icing sugar in the bowl of a mixer with a paddle attachment and beat them on medium speed for about 3 minutes, or until the mixture is very smooth. Add the vanilla extract. Then reduce the speed to low and add the salt and flour, mixing only until just incorporated.

Flatten the dough into a disk, wrap it in plastic wrap, and chill the dough in the fridge for at least 1 hour.

Roll out the dough into a 0.5 cm – ¼ inch thick sheet. Cut into 4 cm rounds using a lightly floured cookie cutter.

Place the cookies on a tray lined with baking paper and place in the fridge for 15 minutes (this will help the cookies retain their shape when baked).

Bake in a preheated oven at 170°C / 340°F on the middle rack for 13 to 15 minutes. The cookies should remain pale.

Transfer them to a wire rack to cool completely.

Heat the cream in a saucepan until warm.

Pour half the warm cream onto the cornstarch and mix until completely dissolved, then sieve it and add it to the remaining cream. Cook for one minute. Make sure to stir well so you do not get any lumps.

Now add the melted white chocolate and mix well. Cook for another minute. Then transfer it to a bowl, cover it with cling wrap (so that the cling wrap touches the ganache), and keep it in the fridge overnight.

The next day, whip the cold ganache with an electric whisk until light and fluffy.

Pipe the whipped ganache with a piping bag (and a round nozzle) onto the shortbread cookie bases and add the mini chocolate chip eyes.