Peel, core and chop two of the apples and cook in half the butter and sugar until puréed. Peel and quarter the remaining apples then cut each quarter into four or five slices. Melt the remaining butter and toss the apple slices in this for a few minutes until just softening. Add the apple purée and bring to the simmer. The filling is now ready.
Allowing three pancakes per portion, divide the purée between the pancakes and either fold them in half or in quarters. Sit them in bowls and sprinkle with the remaining icing sugar. They can now be glazed under a hot grill to give a crispy topping. You can serve them with clotted or double cream, but here are a few ideas of how to enhance all the flavours.