Add all crust ingredients to a bowl and mix until a firm dough forms. Chill for 1 hour.
Roll the dough out slightly larger than your tart pan and line the pan with the dough. Trim the edges.
Place a sheet of parchment paper over the dough and add baking weights. Bake at 350°F/180°C (conventional oven) for 20 minutes.
Remove the weights and parchment and bake another 5-10 minutes, until lightly golden.
Filling
Whisk the egg yolks and sugar together in a bowl.
Combine the cream and vanilla seeds in a saucepan. Heat until just at a boil, stirring often.
Remove from heat and slowly pour into the egg mixture while whisking continuously.
Place the tart crust back in the oven. Pour the filling into the crust and carefully slide the tart into the oven.
Bake for 30-35 minutes at 300°F/150°C, until set but still slightly wobbly in the center.
Cool completely, then refrigerate for at least 3 hours, overnight is even better.
Before serving, sprinkle a layer of (cane) sugar over the top and caramelize it with a kitchen torch (or under the broiler) until crisp and golden.
How to store
Without the caramelized sugar topping, the tart can be stored in the refrigerator for up to 2 days. Once torched, serve immediately for the best crackly texture.