4 tbsp finely chopped fresh chives
150g/5½oz baby spinach leaves
250g/9oz plain flour
1½ tsp baking powder
1 tsp salt
1 tbsp white wine vinegar
125²µ-150²µ/4½-5½´Ç³ú butter
200g/7oz crème fraîche
3 free-range eggs
4 duck eggs
425ml/15fl oz milk
150g/5½oz sliced smoked salmon, to serve