From excavations we know that pit cooking was a cooking method widely used in the Viking Age. To make a cooking pit or earth oven dig a hole which is 1 m broad and 0.5 m deep. The turves from the hole plus an equal amount are later to cover the pit.
Line the pit - bottom and sides - with stones the size of a big fist. Put the stones as close together as possible. Avoid using flint stones as they have a tendency to crack when heated.
Build a fire in the pit. You will need quite a lot of firewood - at least a couple of big baskets full of wood. When the fire is burning, add more stones to the fire. After a couple of hours the firewood will have burnt down to coals and the stones will all be very hot, but before then you need to prepare the meat.
The meat may be a boned leg of lamb, pork, veal or poultry. Rub the meat with a generous amount of salt, fresh herbs and garlic.
Wash some dock leaves, burdock leaves, turnip leaves or plaintain. Tightly wrap up the meat and herbs in leaves and tie the 'parcel' with lime bast.
When the stones are sizzling hot you need to move the top stones and the live coals to the sides. At this stage it's necessary to work fast for the pit not to lose in temperature.
Cover the hot stones lining the bottom of the pit with wet grass. Place the parcel of meat onto the grass and move the hot stones back to cover the parcels completely.
Next, cover the stones with two layers of turves. The first layer with the grass-side down. The second layer with grass-side up.
Allow 0.5 hour plus 1 hour per kilo of meat in cooking time. Then remove the parcel of meat from the oven, discard the burnt leaves to reveal the tender meat inside.
The temperature in a pit oven can reach about 200 degrees centigrade, which kills the soil bacterias.