Crumble-topped fish pie with soft-boiled eggs

Method

1. Heat the oven to 200°C/180°C fan/gas 6. Put the cod in a non-metallic bowl, cover with the salt, then leave for 20 minutes (see Know-how). Thoroughly rinse the fish, then pat dry.
2. Meanwhile, heat a glug of oil and the butter in a flameproof casserole over a medium heat. When the butter has melted, add the onion and leeks and fry for 10 minutes or until softened. Stir in the garlic, mustard, flour and cayenne pepper, then cook for 1 minute. Add the wine and beat with a wooden spoon until smooth.
3. Slowly stir in the stock, cream and juice of ½ lemon and cook, still stirring, for 5–10 minutes until the sauce is thick enough to hold its shape (see tip). If it isn’t quite there, turn the heat to low and keep stirring. Taste and add more lemon juice if it needs it.
4. Turn off the heat, then stir in the fish, prawns and parsley. Pour into the baking dish(es).
5. Boil the eggs in a large pan of water for 5 minutes, then drain and run under cold water until completely cold. Carefully peel the eggs, then place them whole in the baking dish, spaced evenly over the pie filling.
6. Mix the flour with the butter in a large mixing bowl. Stir in the oats and season well. Sprinkle the crumble mixture over the filling as best you can (there will be a few gaps), then grate over the parmesan. Bake the pie for 40-45 minutes until the crumble is golden and the filling is piping hot.