1 onion, finely chopped
2 parsnips, peeled and cut into 1cm cubes
2 sage leaves, finely chopped
1 sweet potato, peeled and cut into 1cm cubes
1 tsp fresh thyme leaves, plus 12 thyme sprigs to garnish
225g/8oz plain flour, plus extra for dusting
salt and freshly ground black pepper
30g/1oz blanched hazelnuts, roughly chopped
pinch salt
150g/5½oz cold butter, cut into cubes
10g butter
200ml/7fl oz double cream
2 free-range eggs
50g/1¾oz Parmesan (or alternative vegetarian hard cheese), finely grated
60g/2¼oz Parmesan (or alternative vegetarian hard cheese), finely grated