Preheat the oven to 180°C/350°F/gas 4.
Roll out the pastry and use it to line a 23cm greased tart tin.
Cover with baking paper, fill with dried beans and bake blind for 10 to 15 minutes. Remove the beans and bake again for 15 minutes, or until golden.
Put the creams, sugar and fine sea salt in a pan and bring to the boil. Remove as soon as the mixture boils up.
Once the pan has been taken off the heat, add the butter and snap in the chocolate. Stir until blended.
Then stir in the milk. Keep stirring till it becomes shiny.
Pour the mixture into the tart shell and leave at room temperature for 2 hours to set.
For the Coffee Salted Caramel Sauce:
Stir together the sugar and water in a small saucepan until the sugar is completely dissolved. Place the pan over medium-high heat and bring to a boil.
Without stirring but swirling the pan occasionally, let the sugar boil until it turns amber in colour. Give the pan a few good swirls to make sure it’s evenly cooking, then remove from the heat.
Immediately add the cream, butter, and coffee powder and swirl until the caramel is smooth and uniform in colour. Return to heat and bring to the boil, whisking constantly until smooth.
Whisk in the vanilla and salt, remove from heat, and set aside until ready to use.
For the Campari and Blackcurrant sauce: