Valentines silky chocolate tart

Intructions

1. Combine flour, brown sugar and salt in a medium bowl and rub together to blend evenly and remove any lumps of sugar. Add cold butter and rub it in until well blended and the mixture looks like bread crumbs. Tip the crumbly mixture into an 8-inch round tart pan and press it evenly into the bottom and up the sides. Prick the base a few times with a fork and place the tart pan on a baking sheet. Bake for 10-15 minutes, until lightly golden and fragrant. Transfer pan to a wire rack to cool.
2. For the filling, combine yogurt and sugar in a small saucepan over medium-low heat and bring it just to a simmer.
   Remove from heat and add chocolate. Let stand off the heat for a minute, then whisk until smooth and melted. Beat egg well with salt in a medium bowl. Gradually pour in the chocolate/cream mixture bit by bit while whisking to temper the egg and make a smooth custard.
3. Pour the mixture into the baked crust and place in the oven for 10 minutes. Turn off the oven and leave the tart in the cooling oven for about 10 minutes until the edges are set with maybe a slight wobble in the centre. Transfer to a wire rack to cool completely and then refrigerate at least 2 hours.
4. For the glaze, combine chocolate and hot water in a small saucepan over medium heat and whisk until melted and smooth. Whisk in butter so it becomes thick and glossy.
    
   Pour the warm glaze over the cooled tart, tilting the tart to coax the glaze out to the edges and coat the surface evenly.
    
   Let the glaze set for about 30 minutes and then top with sea salt flakes immediately before serving.