- Approx 750g (1lb 10oz) puff pastry
- 2 salmon fillets, skinned, from a whole salmon around 800g to 1kg (1lb 12oz to 2lb 4oz)
- 400g (14oz) spinach
- Zest 2 lemons
- 3tbsp crème fraîche
- 2tbsp polenta or cornmeal
- 1 free-range egg, beaten
Before you begin making your salmon en croute recipe, heat the oven to 200 C, 180 C fan, 400 F, gas 6. Trim off the tail end of the salmon fillets. Cut off a quarter of the pastry (chill the rest) and thinly roll out on a floured board, to a shape just larger than one fillet. Place the pastry on a baking sheet, bake for 10 minutes, then remove from the oven and flatten gently with a fish slice. Bake for another 5 to 10 minutes until golden, then allow to cool.
Heat a sauté pan and add the spinach, tossing continuously to prevent it catching. When wilted, squeeze out any excess water and put in a bowl. Stir through the lemon zest and crème fraîche. Season well. Set aside.
Sprinkle the pastry base with the polenta and put one fillet, skinned-side down, on top. Season the fish, spread the spinach mixture evenly over it, making a peak in the centre, and top with the other fillet, skinned-side down again. Season again. Roll out the remaining pastry to about the thickness of a £1 coin. Brush the edges with the beaten egg and lay over the salmon, egg-washed side down. Tuck the edges under the base. The egg wash should stick the edges and form a seal. If the base is crumbling, use a fish slice to hold it up while you tuck in the pastry.
Scallop the edges by pushing back the pastry with a wooden spoon handle, held between your first and middle finger, and brush all over with the beaten egg. Chill for at least 30 minutes. Glaze with the egg wash again and bake for about 30 minutes, covering the pastry with foil if it starts to become too dark. Serve with green veg and buttered new potatoes, or freeze for up to one month wrapped in foil. If cooking from frozen, heat the oven to 220 C, 200 C fan, 425 F, gas 7, and cook straight from the freezer for around 1 hour, covering with foil after 30 minutes.