Finely chop the onion and dill, put it in a saucepan and add salt and citric acid. Chop the greens with a pestle. We need to squeeze the juice out of the greens, not make a puree, so without fanaticism. Next, put the sour cream and pour in portions of water, stirring constantly, until the sour cream completely dissolves. Try for salt and acid, add more if necessary.