1. Heat the oven to 160C, 140C fan oven, gas 3. Lightly oil and line the base of a 20cm sandwich tin with baking paper.
2. Add the melted fat to the biscuits and stir well to mix. Spoon into the tin and, with the back of spoon, spread in an even layer over the base. Chill for 15 minutes.
3. Beat the cheese, yoghurt, fromage frais, vanilla, sugar and orange zest together until smooth. Beat the cornflour and the egg until smooth and stir into the mixture.
4. Pour the mixture over the biscuit base and bake for 40 minutes or until the edges are firm but the centre is still a little wobbly. Turn off the oven, leave the door open ajar a little and leave the cheesecake in the oven to cool for about 3 hours
5. Chill the cheesecake for at least 15 minutes and up to 3 days (without the topping) before serving. Top with a generous mixture of fruits, tossed together with the remaining orange juice.