Ingredients

• 300 g dried pasta — penne or macaroni300 g
• 50 g butter50 g
• ⅓ cup plain flour50 g
• 600 ml full-cream milk600 g
• 1¼ cups grated cheddar120 g
• 2 × 185 g tins tuna in springwater, drained425 g
• 1 cup frozen peas150 g
• 3 spring onions, sliced40 g
• ⅓ cup breadcrumbs40 g
• squeeze of lemon15 g

Method

1. Heat the oven to 200°C fan-forced. Cook the pasta 2 minutes short of the packet time — it will finish in the oven. Drain.
2. Melt the butter in a saucepan over medium heat. Add the flour and whisk it in, then keep cooking for a full 2 minutes, stirring. This cooks out the flour taste; skipping it is why home mornay sometimes tastes pasty.
3. Take the pan off the heat and add the milk in three goes, whisking smooth after each addition before adding more. Lumps form when you add it all at once.
4. Return to medium heat and cook, stirring constantly, for 5–6 minutes until it thickens enough to coat the back of a spoon.
5. Off the heat, stir in two-thirds of the cheese until melted. Season well with salt and pepper — a mornay needs more salt than you think.
6. Fold in the pasta, tuna, peas and spring onions. Break the tuna into large flakes rather than stirring it to mush, and add a squeeze of lemon.
7. Tip into a baking dish, scatter the remaining cheese and the breadcrumbs over the top.
8. Bake for 20–25 minutes until the top is golden and the sauce is bubbling at the edges. Rest for 5 minutes before serving.