Ingredients

3 tbsp butter

2 tbsp plain flour

2 ½ cups milk

1 can tuna, 6 oz. can, drained, flaked

½ cup grated parmesan, plus ¼ cup extra

1 grated lemon zest

4 ½ cups potatoes, peeled, cut into slices

7 oz. baby spinach leaves, chopped

1 onion, finely sliced

Preparation

Preheat oven to 350°F. Lightly grease an 8-cup baking dish.

In a medium saucepan, melt butter on high. Stir in flour and cook for 1 minute.

Remove from heat and gradually mix in milk until smooth.

Return to heat and cook, stirring until the sauce boils and thickens. Simmer for 3 minutes.

Stir in tuna, parmesan and zest. Season to taste.

Arrange half of the potato slices in a deep baking dish.

Layer with half the spinach and onion, with one-third of the tuna mixture.

Repeat layers, finishing with the tuna mixture.

Cover with foil and bake for 30 minutes.

Uncover and sprinkle with extra parmesan.

Bake a further 15 to 20 minutes until the potato is tender and top is golden. Serve.