Preheat oven to 200°C (400°F). Grease a large baking pan with sides, set aside.
Heat oil in a small fry pan over med-high heat. Add chopped onion and sauté until soft and translucent, approx. 2-3 minutes. Remove from heat and set aside.
Pour cream into a pouring jug and stir through parsley, nutmeg, salt and pepper until well combined.
Slice potatoes into approx. 5mm (2cm) rounds.
Arrange a layer of potatoes in greased pan and sprinkle over half of the cooked onions. Pour half the cream over the potatoes.
Arrange remaining potatoes in another layer on top and sprinkle over remaining onions. Pour over remaining cream.
Bake for 35-45 minutes or until potatoes are tender and golden. Remove from oven and sprinkle over grated parmesan, return to oven and bake for a further 10 minutes or until cheese has melted and golden.
Remove from oven and serve.
Enjoy!
Notes
Store leftovers in an airtight container, refrigerated, for 2-3 days.