1 tbsp dill, finely chopped
6 small sprigs dill, to garnish
1 leek, trimmed and thinly sliced
1 heaped tsp grainy mustard
30g/1oz plain flour
55g/2oz unsalted butter, plus extra for greasing
50g/1ΒΎoz mature cheddar cheese, grated
2 tbsp double cream
3 sheets ready-made filo pastry (each measuring about 48x25cm/19x10in)
150ml/ΒΌ pint milk, warmed
225g/8oz fresh salmon fillet, skinned and cubed
50ml/2fl oz dry white wine