Heat the oil in a large pan. Add the onion and bacon and brown for 5 minutes. Add the garlic and cook for a further 2 minutes, then pour in the stock and add about three-quarters of the shelled beans. Bring to the boil and simmer gently for 30 minutes. Blend until smooth.
Add the remaining broad beans and simmer for a further 5 minutes. Season with salt, pepper and parsley, mix well and serve.