Preheat the oven to 150°C/gas mark 2

Line a loose-bottomed fluted flan tin with the ready-rolled pastry, pushing it carefully into the edges and leaving about 2cm overhang all the way around. Line the pastry with baking paper and fill with baking beans. Blind bake for 30 minutes

Meanwhile, add a dash of sunflower oil to a pan and place over a medium heat. Gently sweat down the sliced leek for 5 minutes without allowing it to colour. Season lightly, then set aside and allow to cool

After 30 minutes, remove the pastry case and increase the oven temperature to 165°C/gas mark 3

In a large bowl, mix together the cream, whole eggs and 4 of the egg yolks. Pass the mixture through a fine sieve to help break up the eggs and ensure there are no bits of shell. Stir through the cayenne pepper, nutmeg, Parmesan and a little pinch of salt

Remove the baking beans and paper from the pastry case. Trim the overhanging edges and check for any gaps in the base (these can be filled with a little extra raw pastry if needed). Beat the remaining egg yolk and brush over the base. Place the empty glazed case in the oven for 2 minutes to seal

Mix the cooled leeks and smoked salmon pieces through the cream mixture until evenly combined. Remove the glazed pastry case from the oven and pour in the cream mixture. Return to the oven and bake for 1 hour until golden and firm

Allow the cooked quiche to rest for at least 30–45 minutes before removing from the tin and cutting into slices to serve