Pre-heat the oven to 190℃/375℉ fan or 210℃/410℉ static.
Put the chicken in a large roasting tray and season it with salt on both sides. Finely chop the rosemary and sprinkle it over the chicken then add 3 garlic cloves (skins left on). Drizzle the chicken with olive oil and rub it all over. Bake for 35 minutes.
Meanwhile, add the Nduja to a bowl and add 1 tablespoon of hot water. Mash the Nduja with a fork until it becomes softer and easier to spread. Add another tablespoon of hot water if needed. NOTE: if you use Nduja from a jar you won’t need to do this step, as it’ll already be quite loose.
Remove the chicken from the oven and spread the Nduja over the skin. Bake in the oven for another 10 minutes. Remove from the oven and let it rest while you make the gremolata.
Put the parsley, 1 peeled clove of garlic and the zest of half a lemon on a chopping board and chop it all as finely as possible with a sharp knife. Sprinkle over the chicken and serve.
Notes
Storage - will keep well in the fridge for up to 3 days. Can be reheated in the oven (covered with foil) until hot throughout (180 °C/350°F for 10-15 minutes) or eaten at room temperature.