Start by cutting the stems from the leaves. Cut the leaves in large chunks and the stems in pieces of about 2cm and keep aside separately.
Get a large pot or casserole, fill it up by 2/3 and place on high heat. Bring to a boil and add the stems cooking for a total of 8’. Remove to a colander and allow to drain.
In the same pot add the cut leaves and cook for 6’. Remove from the water and make sure that you get rid of most of their water.
Add both stems and leaves into a serving plate, pour the vinegar and drizzle with the oil. Sprinkle the coriander and season with the salt and pepper.