Melt the butter gently.
Bush the sheets of filo and fold each in half.
Cut in quarters (you will have 12 squares/each pie will be made up of of these squares), then layer quarters over top of each other slightly off-set from the ones underneath.
Brush four large muffin cups, gently press the stack of squares into the muffin tins.
Quarter the apple and remove the core.
Cut each quarter into 6 slices.
Divide the frangipane mix between the muffin cups, top with apple slices.
Bake for 20-25 minutes or until set.
Stand for 5 minutes before removing from the tins.
Serve with whipped cream.