175 g (6 oz) short-cut macaroni, or other short pasta shapes
3 tbsp vegetable oil, plus extra for brushing
1 onion, chopped finely
3 rashers unsmoked collar or back bacon, rind removed, chopped
125 g (4 1/2 oz) button mushrooms, sliced thinly or chopped
175 g (6 oz) 3/4 cup cooked chicken, diced
175 ml (6 fl oz) 3/4 cup creme fraiche
4 tbsp dry breadcrumbs
60 g (2 oz) 1/2 cup mature (sharp) Cheddar, grated
salt and pepper
flat-leaf parsley sprigs, to garnish