Heat 2 tablespoons of oil in a large pot over medium heat. Add the chopped onions and fry until golden, about 15 minutes. Add the barley and 9 cups of warm water. Cover the pot and simmer over medium heat for 45 minutes. Add the diced beets, salt and pepper. Cover the pot and cook for 30 minutes, stirring occasionally.
Then add the green onion, parsley and coriander. Add more boiling water if needed. Cook covered for 60 minutes, stirring occasionally. Add lemon juice and cook for 20 more minutes. Add the whipping cream (optional) and cook for 10 minutes. Taste and adjust seasoning.