Put the potatoes into a pot, add the bay leaf, salt, and cover with water. Bring to a boil over heat and cook until the potatoes are tender, about 15-20 minutes. Drain them well and remove the bay leaf. In a pan heat the cream and butter. Put the potatoes through a food processor or mash with a spoon into a bowl. Add the hot cream and season with salt and pepper. Mix everything well together with a spoon and add the fresh coriander or chives.