Greek recipes that call for yogurt—like tzatziki—typically require Greek-style yogurt, which has been drained of its liquid whey. You can easily make a Greek-style yogurt at home by draining American yogurt. If you start with a high-quality whole-milk yogurt such as Brown Cow, the results will be excellent. While drained Brown Cow may not equal the ultra-creamy texture of award-winning Fage, it outperforms many mainstream alternatives and is a great option for home cooks.
To drain yogurt you will need a bowl, a colander, some cheesecloth, and of course, yogurt.
Place the colander inside the bowl and line it with cheesecloth. Cut a length of cheesecloth that covers the colander with a little overhang. Open it up and fold it in quarters—first in half crosswise and then in half lengthwise—so the cloth forms a neat pouch to hold the yogurt.
Pour the yogurt into the cheesecloth-lined colander. If your yogurt is a cream-on-top style, you can remove the cream layer first and set it aside; add the yogurt to the cheesecloth, then place the cream back on top so it won’t be absorbed by the cloth.
Bring up the edges of the cheesecloth to cover the yogurt, then transfer the whole setup to the refrigerator. Let the yogurt drain for a few hours or overnight, depending on how thick you want the final product. In cool weather you can leave it at room temperature for a shorter period, but refrigeration is the safest option.
As the whey drains away, the yogurt will reduce in volume—typically around half—resulting in a richer, thicker yogurt that works well in dips, sauces, and other Greek-style dishes.
Starting with a good-quality yogurt matters. A large container of Brown Cow often costs less than a smaller container of Fage. After draining Brown Cow you’ll usually end up with roughly the same amount of thick yogurt as a small Fage container, but at a lower price. You’ll also gain about one to one-and-a-half cups of whey, which is useful in baking bread, smoothies, or other recipes that can benefit from the liquid’s mild tang and protein.