Heat the oven to 190°C (Gas Mark 5 / 375°F).
Next, peel the apples. Remove the cores, and cut the flesh into chunks. Remove both ends from the pears, and dice the flesh (I left the skins on mine).
Toss the fruit with the orange juice, caster sugar and cinnamon, and transfer to a baking dish. Bake for about 30 minutes, until the fruit is fairly soft.
While the fruit is baking, prepare the cobbler topping. Add the butter, self-raising flour, and caster sugar to a bowl, and rub together with your fingertips. When the mixture resembles breadcrumbs, add the Greek yogurt and egg, and mix until it just comes together into a soft dough (I found it easiest to use my hands for this).
Remove the fruit from the oven, and add the cobbler mixture in large dollops. Don’t worry about spreading it around.
Return to the oven for a further 30 minutes, until the topping is golden brown.
Serve with cream or custard.