Peel the potatoes. Partially cut into them, then pull them apart into chunky, uneven-edged pieces around 3cm in size. Cut the chorizo to half the size of the potatoes.
Put the olive oil into a big pan on a medium heat, then add the onion and cook gently for about 15 minutes, without colouring. Add the chorizo and when it starts to caramelize, add the potatoes, bay leaves and wine. Cook until the wine has evaporated, then add the chicken stock and/or water and season.
Half cover the pan with a lid, and continue cooking on a low-medium heat. The more slowly you cook it, the more starch will come out of the potatoes – it should take about 25 minutes. When the potatoes are cooked through, add the chopped parsley.
Serve with a drizzle of olive oil to finish, and bread to dip.