2 large leeks, washed and roughly sliced
1 orange, juice and finely grated zest only
2 tbsp roughly chopped tarragon
500ml/18fl oz chicken stock (or 250ml/9fl oz leftover gravy and 250ml/9fl oz stock)
400g/14oz plain flour, plus extra for dusting
3 tbsp plain flour
1 heaped tsp wholegrain mustard
pinch of salt
salt and white pepper
50ml/2fl oz medium sherry
65g/2录oz chilled butter
160g/5戮oz frozen butter
45驳/1陆辞锄 butter
200ml/7fl oz single cream
250g/9oz cooked ham, cut into bite-sized pieces
1 free-range egg, beaten for egg wash
600g/1lb 5oz leftover turkey meat, cut into bite-sized pieces