Thoroughly clean the heads and boil them in a pressure cooker for about 40 minutes. The younger the lamb is, the faster it boils. Then leave to cool and remove the meat, brain and tongue from the heads.
Peel the membranes of the tongues and chop everything. Preheat a few tablespoons of butter and fry the chopped onion and garlic. Mix the meat with the lamb heads with the fried onions and garlic in a tray.