Combine the flour, sugar and salt together.

Add in the butter and work with a fork or pastry blender until the mixture resembles coarse breadcrumbs. You can also do this step in a food processor.

Stir in the egg yolk and work it in to combine.

When the egg yolk is incorporated and the dough is clumpy, turn it onto a work surface knead quickly to incorporate. Don’t work it for too long as that defeats the purpose of having cold butter.

Press the dough onto the bottom of a 9 inch tart shell with a removable bottom. You can also wrap it up into a ball and refrigerate, then roll.

Place the tart into the freezer for 30 minutes, or chill for 3 hours or up to 2 days. In the meantime, preheat the oven to 375 F or 200 C.

Butter a side of foil and fit it tightly against the chilled crust. Bake for 25 minutes, remove the foil, press down any puffed up bits and place back into the oven for 3-5 minutes or until the edges are a light golden brown.

Cool before filling.

In a saucepan over medium heat, stir together the granulated sugar and corn syrup. Keep stirring till the mixture turns a dark amber color.

Quickly add the butter and heavy cream- it will bubble furiously, so be careful. Once incorporated, take the pan off the heat, add in the salt, and pour onto the crust. Let it set completely before topping with the ganache and nuts.

To make the ganache:

Place the chocolate into a heatproof bowl.

Heat the heavy cream in the microwave or in the saucepan until it comes to a boil.

Pour the cream over the chocolate and let it sit for several minutes before stirring.

Stir with a whisk to combine.

Pour the ganache over the caramel mixture.

In a saucepan over medium heat, combine the granulated sugar and water, stirring with a wooden spoon just until the sugar is dissolved.

Add in the nuts and swirl the pan as opposed to stirring, until the mixture turns an amber color and the nuts are toasted, about 10 minutes. At the 5 minute mark, the mixture may start to crystalize and the sugar will get hard. But don’t worry as the crystals will melt, the mixture will begin to caramelize and the nuts will toast.

When the nuts reach a caramel color, take the mixture off the heat and stir in the butter.

As soon as the butter is melted, spread the mixture into an even layer onto a pre-prepared baking sheet lined with parchment paper. Work quickly as the nuts harden immediately.

After around 20 minutes, peal the caramelized nuts and break them into chunks.

Sprinkle these chunks onto the chocolate ganache and refrigerate the tart for 3 hours or until ready to serve.