Combine the apples, butter, sugar and cinnamon in a medium-sized pot and allow to cook, covered, over a low heat for 7-10 minutes until the apples have softened but don’t break apart. Set aside to cool.
Make custard according to the package instructions. It should have a thin runny consistency.
Line a serving dish or bowl with marie biscuits.
Pour 1/3rd of the hot custard over the biscuit layer.
Layer again with biscuits and cover with another custard layer.
Now lay the apple slices and pour the remining custard on top.
Crush the remaining marie biscuits roughly by placing them in a resealable bag and bashing them with a rolling pin. Ensure the biscuits crumbs remain coarse.
Pour the remaining custard mixture over the apple layer and cover with a densely packed layer of the crushed biscuits. Spread some dried fruits and nuts on top.