Preheat oven to 200°C (180°C fan) mark 6. Grease base and sides of 20.5cm (8in) square baking tin with butter; line base with baking parchment.
Step 2
Put milk and fish into a pan; simmer for 5min to cook fish. Lift fish on to a plate. Strain milk into a jug and reserve; you need 175ml (6fl oz) of liquid – top up with milk if needed.
Step 3
In a large jug, mix eggs, cream, some chopped parsley and seasoning. Pour into lined tin. Flake over fish (discard skin). Cook in oven for 20-25min until set and golden.
Step 4
Meanwhile, melt butter in a medium pan, stir in flour and cook for 1min. Off heat, whisk in reserved milk. Return to heat for 3-5min, whisking, until thick. Season; cool for 10min. Preheat grill to medium.
Step 5
Cut omelette into 36 squares or rounds. Arrange on greased baking sheet and pipe/spoon a dollop of sauce on to each. Sprinkle over Parmesan. Grill until golden, scatter over chopped parsley and serve warm.
An experienced and highly skilled team of food writers, stylists and digital content producers, the Good Housekeeping Cookery Team is a close-knit squad of food obsessives. Cookery Editor Emma Franklin is our resident chilli obsessive and barbecue expert, who spends an inordinate amount of time on holidays poking round the local supermarkets seeking out new and exciting foods. Senior Cookery Writer Alice Shields is a former pastry chef and baking fanatic who loves making bread and would have peanut butter with everything if she could. Her favourite carb is pasta, and our vibrant green spaghetti is her weeknight go-to. Lover of all things savoury, Senior Cookery Writer Grace Evans can be found eating crispy corn and nocellara olives at every opportunity, and will take the cheeseboard over dessert any time (though she cannot resist a slice of tres leches cake). With a wealth of professional kitchen know-how, culinary training and years of experience between them, they are all dedicated to ensuring every Good Housekeeping recipe is the best it can be, so you can trust they’ll work (and if they don’t – we’ll have the answer for why*) every time (*90% of the time the answer is: “buy an separate oven thermometer”!).
