Pour barley grits into a strainer and rinse thoroughly in several waters. Boil some water in a large saucepan, place the strainer with barley grits on top, cover and cook on a medium heat for 20 minutes. Boil 4 cups water, add a pinch of salt, 1 tbsp. vegetable oil and steamed pearl barley. Bring to a boil, reduce heat and cook for 20 minutes. Put pearl barley in a colander. Wash champignons and cut into quarters. Boil in 1.5 cups boiling salted water for 6 minutes. Take champignons out of water with a slotted spoon and put on a cutting board. Strain the mushroom broth. Peel onion, chop and fry in a heated vegetable oil for 4 minutes. Add champignons and fry 3 more minutes. Put the pearl barley, stir and immediately remove from fire. Bring mushroom broth to a boil, add soy sauce and pearl barley with mushrooms and onions. Cover and simmer for 1 hour. You can do it also in the oven.