Quark is a popular soft cheese from Central Europe, and hugely popular in Germany. It’s something between cream cheese and ricotta, but a touch thinner. It is often mixed with herbs and spread on bread, but also used in everything from pancakes to souffles.
Classically, quark is made by heating milk, mixing it with a culture, and then stirring the milk as it curdles. Once the cheese has thickened, it is hung in a cheesecloth bag to allow the whey to drain off, and then it is packed into a small clay or glass pot for storage.
You can also make it with buttermilk that contains live cultures. Leave it overnight in a cool oven (150 degrees C), then let drain in cheesecloth.