1. Preheat the oven to 19OC. Lightly butter a 4-cup-capacity ovenproof baking dish.
2. Place eggs into a saucepan of boiling water and boil for 7 minutes (for cooked through eggs). Drain and run under cold water until cool, then peel. Set aside.
3. Melt the butter in a heavy-based saucepan and add the onion. Cook gently until the onion is soft, about 5 minutes. Remove from the heat, add the flour and stir well to make a roux. Place back over a medium heat, stirring continuously until roux is lightly golden. Pour on the hot milk, stirring continuously and cook until the sauce is smooth, shiny and thick enough to coat the back of the wooden spoon. Season with salt and pepper and stir through parsley if using.
4. Place the fish in the baking dish. Halve or quarter eggs and place on top, then spoon over the sauce.
5. Mix together the breadcrumbs and cheese and sprinkle evenly over the top of the sauce. Place in the oven and cook for 20 minutes until the topping is golden and crisp and the sauce is bubbling around the edges. Serve with a side of steamed green vegetable.

Make it different

• Add 2-3 tablespoons rolled oats to the crumb topping.
• Add vegetables and herbs — celery, spinach, corn and peas.
• Add capers and/or gherkins.

See more of Kathy Paterson's fish pie recipes

• Fish pie 
• Traditional fish pie with a pastry lid