Rinse the ceps under cold running water. Keep in mind that it's best not to wash ceps, because they will soak up the water.
Slice the ceps and reserve. Heat oil in a large pot, medium-high heat, add the barley, stirring, for 1 minute.
Cover the barley with water and add the vegetable stock. Cook around 20 to 30 minutes or until tender.
In a large, deep skillet, heat the extra virgin olive oil. Add the onion and garlic and cook over moderately high heat, stirring constantly, until softened, about 2 minutes.
Add the ceps, season with salt and pepper. Cook, stirring frequently, until tender, about 3 to 5 minutes.
For the end, add the parsley, and mix well.
When the barley are cooked, drain it and add into the mix ceps. Then, add some grated parmigiano reggiano, cream and the buckwheat butter. Mix well to obtain a creamy texture.
Transfer the risotto to a bowl. Garnish with parsley and add parmigiano reggiano shavings. Serve immediately.