Preparation

Preheat oven to 170°C. Melt 40 g butter in a large saucepan over medium heat. Add onions and cook, stirring, for 10 minutes or until golden brown. Set aside.
Lightly grease a 2.5 L baking dish. Layer half the potato slices in prepared dish, then top with onions and anchovies. Add the remaining potato slices.
Place milk and cream in a saucepan and bring just to the boil. Remove from heat, stir in reserved anchovy oil, then pour over potato slices. Scatter with breadcrumbs, then dot with finely chopped remaining 60 g butter.
Bake gratin for 1 hour, then cover with foil and bake for a further 30 minutes or until potatoes are cooked through and tender. Stand for 20 minutes before serving.

Ingredients

  • 100 g butter
  • 3 onions, thinly sliced
  • 1.5 kg (about 6) sebago potatoes, thinly sliced
  • 200 g anchovies in oil, drained, 80 ml (⅓ cup) oil reserved
  • 200 ml milk
  • 400 ml pouring cream
  • 2 tbsp dried breadcrumbs