Corn chowder with chestnut mushrooms and pancetta

4 ears of corn, husked and charred on a grill

100g chestnut mushrooms, sliced thinly, stems reserved

1 red chilli, sliced very thinly

1 red rooster potato, peeled and finely diced

1 medium leek, green parts discarded, sliced thinly

1 garlic clove, crushed

100g pancetta, chopped into small chunks

handful of chopped parsley

2 sprigs of thyme

salt

pepper

60ml white wine

250ml double cream

50g butter

50g Parmesan