1. You will need a double-thick layer of fine-mesh cotton cheesecloth or paper coffee filters. Place this over a colander that does not rust.
2. Place colander in a deep bowl.
3. Pour yogurt into colander and cover with plastic wrap.
4. Refrigerate for 8 hours or overnight.
5. Discard drained liquid and place yogurt in a small bowl.
6. Cover, refrigerate, and use when needed.