Place Dr. Oetker Nona Tarts, butter and egg in a mixing bowl. Mix well.
Transfer the tart mixture into a 22cm tart pan one handful at a time, pressing it down to create an even, thin layer over the entire pan, about 0.5cm.
Use a fork to prick the bottom of the tart shell.
Bake at 180°C for 20 minutes or until golden brown, set aside to cool.
Place cream cheese, greek yogurt, orange zest, orange juice, vanilla flavour and sugar in a mixing bowl. Mix at medium speed, until smooth.
Transfer yogurt mixture into tart crust.
Starting from the outer edge, place mango slices in a circular pattern, making full rotations all the way to the center.
Chill the mango tart fro at least an hour before serving.
1 box of Dr. Oetker Nona Tarts makes two 22cm tart shells.