Grease a 20cm loose-bottomed tart tin.
Roll out the sweet pastry on a lightly floured surface to line the tin.
Press the pastry into the tin, trim the edges, and chill in the fridge for 30 minutes.
Preheat the oven to 180°C.
Line the pastry with parchment and baking beans.
Bake blind for 15 minutes, remove beans, and bake for 5 more minutes until golden.
Reduce the oven temperature to 170°C.
Melt the chocolate in a heatproof bowl over simmering water.
Whisk cream and egg yolks into the melted chocolate.
Pour the mixture into the tart case and smooth the top.
Bake for 15 minutes until set and cool to room temperature.
Line a 23cm square baking tray with parchment.
Whisk 350ml water, cornflour, and cream of tartar in a pan until thickened over medium heat.
Boil sugar, 200ml water, and lemon juice in another pan to 116°C.
Combine both mixtures and simmer on low for 30 minutes until light golden-brown.
Stir in the rosewater.
Pour into the tray and chill in the fridge for 2 hours until set.
Turn out the Turkish delight onto sugar-dusted parchment and cut into squares.
Dust one third of the squares with icing sugar.
Coat the remaining squares in melted chocolate and chill until set.
Serve tart slices with three pieces of Turkish delight and vanilla ice cream.