Millionaire's shortbread

Preparing the shortbread:

1. 1Preheat the oven to 180°C.
2. 2Line a 23x23 cm square baking pan with parchment paper.
3. 3Whip the butter with an electric mixer until creamy and even.
4. 4Add the sugar and salt.
5. 5Beat the mixture until light and airy.
6. 6Add the vanilla extract and egg yolk, then mix until incorporated.
7. 7Add the flour in several additions and mix until incorporated.
8. 8Transfer the shortbread mixture to the prepared pan, then flatten it evenly to form a uniform layer.
9. 9Bake at 180°C for about 20 to 25 minutes, or until the edges are golden.

Preparing the caramel:

1. 10In a saucepan, combine the butter, sugar, salt, vanilla extract, sweetened condensed milk, and honey, then heat over medium heat.
2. 11Place over medium-low heat and whisk until the mixture melts and is smooth.
3. 12Continue whisking for about 5 to 6 minutes, until the caramel starts to thicken and pull away from the sides.
4. 13Pour over the shortbread base, smoothing to the edges to create a flat layer.
5. 14Chill in the refrigerator for about 15 minutes to let the caramel set.

Preparing the chocolate ganache:

1. 15Chop the chocolate and melt it with the cream in a double boiler.
2. 16Pour the chocolate over the caramel and smooth into an even layer. Sprinkle with salt if desired, then chill and cut into pieces.
3. 17Chop the chocolate and place it in a bowl.
4. 18In a saucepan, heat the cream over medium heat until it starts to simmer.
5. 19Pour the hot cream over the chopped chocolate.
6. 20Let sit for 1 to 2 minutes to allow the chocolate to melt.
7. 21Gently mix with a spatula or whisk until you get a smooth, glossy texture.

Final assembly:

1. 22Pour the chocolate over the caramel and smooth into an even layer.
2. 23Sprinkle with flaky sea salt.
3. 24Refrigerate for 2 hours and cut into pieces.