Get a food processor when you subscribe to our print magazine
Rinse and drain the beans, then pat dry with kitchen paper. Mix the onion with the vinegar and leave for 5 mins to soak. Mix the mushrooms and parsley into the beans, then add the onions and vinegar, oil and seasoning, then mix well.
Arrange overlapping slices of chorizo over two plates and spoon the salad in the centre. Serve with crusty bread.