Nope, we're not talking subatomic particles here. We're talking cheese! Fresh cheese! The original cream cheese, in fact. Ever had quark?
Quark is actually a bit thinner and creamier than cream cheese, landing somewhere between cream cheese and sour cream in consistency. Quark is still perfectly spreadable on bagels and crackers, but also gets some major points for versatility. It can be substituted for cream cheese, sour cream, or yogurt in any recipe, and its milk, tangy flavor makes a great addition to dishes like quiche, dips, sauces, and casseroles.
And yes, quark is naturally low in fat, making it very handy when we want to save a few calories without sacrificing flavor. Some quark producers will mix in cream to give the cheese extra richness, so check the labels if a lower-fat product is what you're after.
This is a fresh cheese traditionally made by adding acid to milk, though many commercial dairies now use rennet. The curds are stirred as they form, which gives quark its creamy texture. Afterwards, the quark is partially drained of whey to make it thicker. If it is fully drained of whey, quark takes on a more compact and crumbly texture closer to queso fresco or feta.
You're not likely to find quark at the grocery store, but check with artisan cheese producers at your farmers market. This quark will be uber-fresh and will keep in your fridge for about a week.
How do you cook with quark?
Related: Make Cheese at Home: Fresh Buttermilk Cheese