To make the creamed spinach:
- Boil the kettle. Put the spinach into a heatproof bowl and cover with the hot water. Give it a stir. Once wilted, drain with a colander and set aside to cool.
- Melt the butter in a saucepan with the oil. Once the butter starts to bubble, add the shallots and gently cook for five minutes until softened. Add the garlic,
- Cook for a further two minutes.
- Whisk in the flour, pour in the milk and whisk until combined. Turn the heat down to low and allow the milk to thicken.
- Meanwhile, squeeze the excess liquid from the spinach and roughly chop. Stir the spinach into the onions with the single cream. Grate some fresh nutmeg over, and season with salt and pepper.
- Transfer the creamed spinach to the bottom of the pie dish.
To make the fish pie:
- Heat the oven to 200°C/180°C fan/gas mark 6.
- Melt the butter in a saucepan, stir in the flour and cook for two minutes. Add the milk, stock and mustard, and stir until thickened.
- Remove from the heat, stir in the parsley and dill, and season with salt and pepper.
- Gently add the fish and prawns and spoon it over the creamed spinach.
- Unroll the puff pastry and lie over the pie dish. Get creative with different biscuit cutters to layer the pastry, or use a small sharp knife to score lines in it.
- Brush with the beaten egg wash. Bake in the oven for about 40 minutes, or until the pastry is golden brown.
- Serve with seasonal vegetables.