Cook potatoes on a tray of rock salt. Scoop out and pass through a mouille. Add Butter and Cream. Add finely sliced Spring Onions and slice Calvo Nero. Roughly cut parsley and season, dress with Olive Oil.
For the ham hock:
Combine the hocks, vegetables, bay leaf, thyme and rosemary in a large pot. Cover with the cider and chicken stock. Bring to the boil then reduce the heat and simmer, covered, for about 3 hours, or until the meat is falling off the bone. Let the hocks cool in the stock. Lift out and pick the meat off. Discard the bones.
Combine ham hock into the colcannon and mix thoroughly.