Beef Tongue a la Caucasus

Ingredients for 8:

4 lb beef tongue
1.5 lb fresh mushrooms
10 tbsp vegetable oil
4 shallot onions
2 cups peeled walnuts
5 garlic cloves
2 cups sour cream
Italian parsley, or parsley
Salt and ground black pepper on taste

Method:

Boil beef tongue for about 3 hours in a large saucepan.
Then, drain and add cold water in the saucepan. Let stand for 5 minutes, then drain, to remove skin easily.
Cut the tongue into medium cubes, and place in the saucepan.
Cut mushrooms and onions, and stir-fry with vegetable oil in a deep skillet, until onions turn golden colored.
Remove the oil, and add the mix to the tongue. Stir well.
Grate walnuts and garlic together until an even consistency.
Mix them well with sour cream, salt, and ground pepper.
Pour the mix into the saucepan with the tongue stirring well.
Stew all together on low heating for about half an hour, or on your taste.
Cut parsley greens, and sprinkle every portion with the greens when serving.
Serve with your favorite garnish.