2 large leeks
5 tbsp chopped fresh tarragon
salt and freshly ground black pepper
500g/1lb plain flour
50g/2oz plain flour
pinch salt
1 tsp white wine vinegar
125g/4oz unsalted butter
75g/3oz unsalted butter
1 egg, beaten
125g/4oz lard
350ml/12fl oz whole milk, warmed
2 x 150g/5oz chicken breasts, cut into chunks
125g/4oz good-quality ham, cut into strips