Use a large bowl to mince the meat.
Use another bowl to have some bread soaked in milk, then drain the liquid.
Heat a pan on the stove to a medium heat and melt the butter and add the chopped onion. Saute it until the onion gets translucent.
On a cutting board finely chop the dill. Then in a small bowl add two eggs and whisk.
Now combine the minced meat, the bread, and the the onion with the eggs transfer them to the pan and season with salt and pepper and one-third of the dill.
Have a small cup with flour and the chopped dill. You can leave a little dill for the end.
Have some flour on your hands wet them with a little vinegar and form small balls from the meat mixture and roll them in the flour and dill mixture.
You can use same pan and transfer the meat balls ready to fry until brown.
You can place some paper tower at the bottom of a place where you put the ready fried balls to get out any extra oil.
Now it's time to prepare the sour cream by mixing 2 tbsp of the flour with the sour cream, dried mushroom powder and with, rest of the dill.
Transfer the meatball in a serving plate pour over the sour cream mixture.