Walnut-stuffed eggplant rolls

All over the Caucasus, people traditionally stuff eggplants (aubergines) with walnuts and pomegranate seeds to be pickled and preserved for the long winter months. This is a fresh version of the Georgian dish badrijani nigvzit, using grilled eggplant instead, but with the same flavours. Try to use narrow eggplants, rather than bulbous ones, to give you long slices for rolling.