Rösti-topped Fish Pie

Use any sustainably sourced fish you like in this crispy pie.

Hands-on time 30min. Cooking time about 45min. Serves 6 FOR THE FILLING

50g butter

2 leeks, finely sliced 2tsp Dijon mustard 50g plain flour 600ml milk

750g skinless fish fillets, cut into 2cm chunks, we used salmon, smoked haddock and cod 200g frozen peas

FOR THE RÖSTI TOPPING

750g floury potatoes, unpeeled

2tbsp cornflour

5g butter

1 Preheat oven to 200°C (180°C fan) mark 6. For the filling, melt butter in a large pan over medium heat and cook leeks for 10min, until softened. Stir in the mustard and flour and cook for 1min. Remove from heat and gradually stir in milk. Return to heat and cook, stirring, until thickened. Set aside.

2 To make the rösti topping, coarsely grate the potatoes, then pile grated potatoes on

to a clean tea towel. Gather up the corners and squeeze out as much moisture as you can over the sink. Empty squeezed potato into a medium bowl and mix in the cornflour and plenty of seasoning. Melt butter in a large, non-stick frying pan over medium heat. Add potatoes, stir to coat in the butter and fry for 5-10min, stirring regularly, until softened.

3 Stir fish, peas and plenty of seasoning into the leek sauce, then decant into a shallow 2 litre ovenproof serving dish. Top with the rösti mixture in an even layer.

4 Cook in oven for 25-30min, until bubbling and golden. Serve with seasonal greens, if you like.

PER SERVING 496cals, 31g protein, 23g fat (12g saturates), 39g carbs (4g total sugars), 6g fibre

FREEZE AHEAD Prepare to end of step 3; cool leek sauce before adding fish and peas. Cool rösti topping before assembling. Wrap dish well and freeze for up to 1 month. To serve, defrost overnight in fridge. Complete recipe.