1. Cream the softened butter and sugar (sachet 1) for 1 minute until pale and fluffy, then mix in the egg yolk. Add the cookie mix (sachet 2) and combine to form a dough – it should have a crumbly texture but be able to hold its shape when pressed together.

2. Roll the cookie dough into a log, cover in cling wrap or baking paper and allow to chill for 1 hour or more.

3. Preheat the oven to 180° C and grease a muffin pan or moulds.

4. Evenly divide the cookie log into 12 pieces. Transfer to the prepared pan and press into an even layer on the base and sides of the mould. Bake for 20 minutes or until the edges are golden.

5. While the base bakes, make the caramel. Combine the butter, brown sugar, vanilla and condensed milk in a pan and place over medium heat. Whisk until melted and combined, then continue whisking over the heat while the caramel bubbles and darkens in colour. Once it reaches the correct temperature you will see it start to thicken and pull away from the edge, about 5 minutes – your caramel is ready.

6. Pour the caramel onto the shortbread base cups, smooth the edges and create a flat surface. Chill for 10 minutes to allow the caramel to set.

7. Melt the chocolate and cream in a double boiler or by microwaving in 2-3 20-second bursts, stirring in between.

8. Pour the chocolate ganache over the caramel and smooth into an even layer. Allow to chill and then remove from moulds. Sprinkle with flakey salt if desired and serve.