Preheat the oven to 180C/350F/Gas 4.
For the tart, brush the pastry with the olive oil and cut in half. Lightly grease a blini pan and scrunch one piece of the pastry into the pan, then layer the second piece on top. Sprinkle over the icing sugar and place the pan in the oven and bake for 2-4 minutes, or until the pastry is crisp and golden-brown.
Melt the butter in a frying pan and fry the apple pieces and caster sugar, shaking the pan from time to time, until the apples start to caramelise and turn soft.
Carefully remove the tart from the blini pan and fill with the fried apple.
To serve, whip the cream together with the caster sugar until soft peaks form when the whisk is removed from the bowl. Place the tart on a plate, top with the whipped cream and garnish with a sprig of fresh mint.