2 tbsp chopped parsley, plus more for sprinkling
1 banana shallot, finely chopped
750ml/1录 pint light chicken stock
陆 tsp dried chilli flakes
2 cloves garlic, peeled
1 tbsp olive oil
1 tbsp tomato pur茅e
1kg/2lb 4oz small clams, such as palourde
4 tbsp dry red vermouth