1 tsp Dijon mustard
500g/1lb 2oz dried macaroni
100驳/3陆辞锄 plain flour
1 bay leaf
salt and freshly ground black pepper
60g/2录oz white breadcrumbs
pinch freshly grated nutmeg
100驳/3陆辞锄 butter, plus extra for greasing
400g/14oz mature cheddar, grated
75ml/2陆fl oz double cream
1.2 litres/2 pints full-fat milk
50驳/1戮辞锄 Parmesan, grated
100驳/3陆辞锄 smoked bacon lardons or smoked pancetta cubes