Step 1

Preheat oven to 180ºC. Brush a 1.75L (7-cup) capacity baking dish with melted butter. Place the cream, milk and onion in a saucepan over medium heat. Cook for 3-4 minutes or until almost boiling. Remove from heat. Season with salt and pepper. Set aside for 10 minutes to cool slightly. Transfer onion to a plate.

Step 2

Place one-third of the potato, overlapping, in the base of dish. Top with one-third of the onion and one-third of the cheddar. Repeat with remaining potato, onion and cheddar.

Step 3

Pour over cream mixture. Place dish on a baking tray. Bake for 1 hour or until potato is tender and top is crisp and golden. Set aside for 10 minutes to cool slightly before serving.