300g large pasta spirals
1 each leek and celery stalk, thinly sliced
2 tablespoons plain flour
2 cups milk finely
grated zest and juice of 1 small lemon
½ cup grated tasty cheese
425g can tuna in brine, drained, flaked
2 cups plain potato chips, crushed
Preheat oven to 200C (180C fan forced). Lightly grease an 2L capacity ovenproof casserole dish. Cook pasta in a large saucepan of boiling water according to packet directions. Drain, reserving ¼ cup cooking liquid. Return pasta to pan.
Meanwhile, melt butter in a saucepan over medium heat. Add leek and celery and cook for 5 min. Sprinkle over flour and cook, stirring for 1 min. Gradually stir in milk until combined. Bring to a boil stirring constantly until the sauce thickens. Remove from heat and stir through lemon zest and juice and cheese.
Add the sauce mixture to the pasta along with tuna and reserved cooking liquid. Season well to taste. Spoon mixture into casserole dish and sprinkle with crushed chips. Bake in the oven for 12-15 min or until chips are lightly browned.
Garnish with chopped fresh dill and a lemon wedge if desired. Serve with a chopped tomato and cucumber and a garden salad.