Emergency biscuits!

Trying to be efficient today and got my head in and around invoices and PAYE and was actually getting somewhere so I should have known that it wouldn't last. Unexpected visitors planning a visit - in about half an hour, is that ok? Paperwork dropped like a hot potato and oven on!
These are Custard Creams made with my late Godmother's recipe that works a dream. Very simple too!
Just cream 300g butter and 100g icing sugar, mix in 300g plain flour and 100g custard powder. Roll in to balls and put on greased trays. Flatten slightly with a fork and bake at 180 till lightly browned. I put butter icing in middle and then dust with icing sugar to serve.
I would have dusted for guests but unfortunately ran out of time!