Ingredients
Directions
- 1
Boil the potatoes for 15-20 minutes or until soft. Drain and leave to stand for 2 minutes to dry out, before returning to the pan. Add 150ml of the milk, 30g of the butter and plenty of salt and pepper. Mash well and then beat with a wooden spoon to get it smooth.
- 2
Meanwhile, heat 500ml of the milk in a saucepan over a low heat until simmering. Add all the fish and prawns. Everything should be completely submerged in the milk. Lightly poach for 4-6 minutes or until just cooked and flaky. Pour into a sieve over a bowl, separating the fish and milk. I then add the milk to a jug to make it easy to pour.
- 3
Melt the remaining butter in a sauce pan over a medium-low heat. Add the flour and mix well. Whisk in the milk that was used to poach the fish, a little at a time, until you have a lovely thick sauce. Reduce the heat to low and cook, stirring occasionally, for 2 minutes to cook out the flour. Add the mustard, lemon zest and juice and plenty of salt and pepper. Mix well.
- 4
Pre-heat the grill to high. Add the fish and peas to 22cmx28cm oven proof baking dish and then pour over the sauce. Shake together and then top with the mash. To get the mash really even, dot the mash around the edges first, then use a butter knife to smooth them out. Spread the mash into the middle with the knife and smooth it over to get an even layer.
- 5
Sprinkle over the cheese and pop under the grill for 8-10 minutes or until the top is a golden and bubbly. Serve immediately.
