In a saucepan, gently saute the apple slices and cinnamon in the two tablespoons of butter. Cook for 10 minutes, until the apple is soft.
Add in the three tablespoons of your caramel sauce and cook for another two minutes. Remove from heat.
Heat your oven to 180 degrees Celsius and line a baking tray with baking paper or grease it.
Take your three sheets of rolled out puff pastry and cut each into 4.
Place a spoonful of apple filling into the middle of each quarter of pastry.
Fold over one corner to meet the opposite corner and crimp it down with a fork. Repeat this until all the filling is gone and you have 12 mini pies.
Brush each mini pie with some egg wash.
Bake for 20 minutes until golden brown, then leave to cool for 10 minutes before smothering with caramel sauce.