300g/10陆oz dried pasta, such as farfalle
salt and freshly ground black pepper
3 tbsp dried breadcrumbs
50g/1戮oz plain flour
freshly grated nutmeg
120g/4陆oz unsalted butter, plus extra for greasing
250g/9oz Gruy猫re, grated
750ml/1录 pint full-fat milk
75驳/2陆辞锄 Parmesan, grated
250g/9oz smoked salmon, cut into strips