Sweet potato casserole

Cut the sweet potatoes into roughly even one inch squares.

Cover them with milk and cream, add a big pinch of salt and cook on a low heat until soft; the milk concentrates and gives toffee notes.

Add brown sugar and a little cayenne.

Add the egg and mash until smooth.

Chop the pecans and fold them in, top with marshmallows and bake.

Cool, portion and freeze dry. Freeze-dried, the marshmallows go dry and chewy and the flavours concentrate.