Bring the lamb to room temperature for three hours before cooking.
Preheat the oven to 180°C.
Fry the lamb in oil for two minutes on each side until coloured and rest for 15 minutes.
Whisk salt and egg whites until light and fluffy to create the crust.
Spread a 1.5 cm layer of salt crust on a tray and place the lamb on top.
Cover the lamb entirely with the remaining salt mixture, ensuring no holes remain.
Bake the salt-encrusted lamb for 50 minutes.
Remove from the oven and rest for 30 minutes inside the crust.
Pound salsa verde ingredients in a mortar until smooth and emulsified.
Cut open the crust, remove the lamb, carve, and serve with salsa verde.