1.Cut pastry into four squares. Roll squares on lightly floured surface until large enough to line four 10cm (4-inch) springform tins. Ease pastry into tins, press into bases and sides; trim edges. Place tins on oven tray; refrigerate 20 minutes.
2.Meanwhile, preheat oven to 200°C/400°F.
3.Melt butter in a large frying pan over medium heat; cook leek, stirring, until starting to soften. Cook, covered, over low heat, 5 minutes or until soft. Transfer leek to a large bowl. Add flaked salmon.
4.Whisk eggs, cream and cheddar in a large jug. Season. Stir through salmon mixture.
5.Line pastry with baking paper; fill with dried beans or rice. Bake 10 minutes. Remove beans and paper; bake for a further 10 minutes.
6.Spoon salmon mixture into pastry cases. Bake for 25 minutes or until mixture is golden and set.
Cool the quiches before packing into airtight containers. Refrigerate for up to 2 days. They are not suitable to freeze. You need four 10cm (4-inch) spring-form tins for this recipe.Note