Boil the milk in a large saucepan with a thick bottom. Make sure the milk doesn’t run away.
When milk starts to move up add kefir, after that smetana and yogurt. Mix well, turn off the burner and set aside for 30 minutes. You will see that milk turn into the inhomogeneous mass. It’s ok.
Line a colander with a piece of cheeseclothes. Transfer the mass to a colander, let the liquid drain.
Put aside for up to 2-4 hours. The time depends on the consistency you want to achieve: the longer the cottage cheese spends in this stage, the drier the product you will get.
Put the quark into a glass container and enjoy the view. Store in the refrigerator.