Put the chopped mushrooms in a bowl, sprinkle with salt and mix gently with your fingertips. It is important not to overdo it with salt, but also not to pour enough – mushrooms should start to give juice. So taste it and adjust it if necessary.
Then add dill, garlic and onion to the bowl, add sugar and lemon juice, pour vegetable oil (it will absorb the flavors of dill, onion and garlic and transfer them to mushrooms) and mix again.
Let stand for 10 – 15 minutes.