Boil or steam potatoes until tender; drain, cool slightly.
Cut top from each potato, scoop out inside pulp and mash well.
Place spinach in dry pan, cook until thawed and all liquid evaporated.
Add cheese, shallots, nutmeg and mashed potato to spinach, mix well.
Spoon filling into potatoes, place each potato on a piece of aluminium foil, wrap securely.
Barbecue until heated through.