Preheat oven to 180°C (160°C fan-forced), lightly grease a 25cm round tart tin with removable base and line base with baking paper.
Place pastry on a lightly floured kitchen work surface. To check if the pastry is the correct size for the tart tin, place the tart tin over the pastry, there should be at least a 2 ½ cm border the whole way around.
Carefully line the tart tin, prick the base all over with a fork, cover and chill in the refrigerator for 30 minutes.
To blind bake the pastry case, line the pastry case with baking paper or foil. Cover paper with baking beans or a dried pulse , fill to the top to help support the sides and weigh the base down during cooking.
Place tart tin on a baking tray in preheated oven, bake for 15 minutes. Remove tart tin from oven, check pastry is lightly golden before removing beans and baking paper.
Return tart tin to oven and cook for a further 15 minutes. Remove tart from oven, allow to cool.
Meanwhile to make the filling, place the chocolate and half the yoghurt together in a small bowl over a saucepan of barely simmering water, stirring until chocolate is just melted.
Add the remaining yoghurt, stirring until combined, the allow mixture to cool to room temperature.
Place the mascarpone in a large mixing bowl and using electric beaters, beat until light and fluffy. Add the white chocolate mixture, stirring until just combined.
Spoon filling into prepared tart shell and smooth top with a spatula. Cover and chill for 2-3 hours.
To serve, carefully place the strawberries on top of the filling. In a small bowl heat the redcurrant jelly in the microwave (on medium) for 30 seconds.
Add orange zest, stirring to combine. Using a pastry brush carefully brush the redcurrant glaze over the strawberries.