For the chocolate pastry
Place the flour, icing sugar and cocoa powder in a bowl. Add the butter and rub into the mixture until it resembles dry breadcrumbs. Add the egg yolk and mix until the mixture just comes together. Turn onto a work surface and shape into a ball. Cover with plastic wrap and chill for at least 30 minutes.
Preheat the oven to 200 °C. Divide the dough into 8 portions. Grease eight 10cm fluted tart tins with removable bases and line with the dough. Chill for 15 minutes and bake blind (see below). Set aside to cool.
Once the tin has been lined with the pastry and chilled for 20 minutes, line the pastry case with baking paper and fill with pastry weights or dried beans. Bake in the oven at 200 °C for 10 minutes. Remove the paper and pastry weights. Reduce the oven temperature to 180 °C and bake for a further 8 to 10 minutes, or until the pastry is cooked through. Remove from the oven.
For the filling
Remove and discard label from the condensed milk tin and make two small holes in the top of the tin. Place the tin in a saucepan with the holes facing up. Fill the saucepan with cold water to reach almost to the top of the tin (±1 cm from the top). Bring to the boil, then reduce the heat to medium-low and simmer for 3 to 3½ hours until a caramel forms on the top of the tin. It’s very important to remember to keep topping up the water to the same level to ensure the pan doesn’t boil dry. Allow the tin to cool completely before opening. Spoon the caramel into a mixing bowl and stir in the sea salt. Divide the mixture amongst the pastry cases, then set aside.
Preheat the oven to 150 °C. Place the chocolate in a heatproof bowl over a pan of lightly simmering water, making sure the bottom of the bowl doesn’t touch the water. Stir gently until the chocolate has melted, then set aside to cool for 5 minutes.
Gently heat the cream and milk in a saucepan over medium heat until just below boiling point. Remove from the heat, stir in the whisked eggs and return the mixture to the heat and simmer over low heat for 4 to 5 minutes. Strain the egg mixture over the melted chocolate. Stir to combine and pour over the caramel tartlets. Bake for 7 to 10 minutes or until just set. Allow to cool completely. Fill a small piping bag with the melted white chocolate and pipe a zigzag pattern over the top of the tartlets. Serve with whipped cream.
Extract from Favourite Desserts, by Clover. Published by Lapa.