Ingredients
Method
1.Preheat oven to 180°C. Lightly grease an 8-cup baking dish.
2.In a medium saucepan, melt butter on high. Stir in flour and cook 1 minute. Remove from heat. Gradually mix in milk until smooth. Return to heat. Cook, stirring, until sauce boils and thickens. Simmer 3 minutes. Stir in tuna, parmesan and zest. Season to taste.
3.Arrange half potato slices in dish. Layer with half spinach, onion and one-third tuna sauce. Repeat layers, finishing with tuna sauce. Cover with foil. Bake 30 minutes.
4.Uncover and sprinkle with extra parmesan. Bake a further 15-20 minutes until potato is tender and top is golden.
Buy a wedge of parmesan rather than packets of ready grated or shaved parmesan. It has a better flavour, is cheaper and will keep for 1 month when wrapped and sealed in a snap-lock bag in the fridge.
Note