Mix the yogurt with garlic and salt (optional). The easiest way is to mix it inside the yogurt container.
Place the yogurt into the cheesecloth. Pick up the edges of the cloth and tie them at the top. Hang the bundle from a kitchen sink faucet or a standing mixer to drain overnight, allowing time to do the hard work for 12 to 24 hours. Position a bowl underneath to catch the draining liquid.
In the morning, the whey strains out, leaving you with a very thick (and delicious) cheese.
Store in the fridge in a closed container for up to 10 days.
To serve, spread labneh on a plate or in a small bowl and top with Za'atar, and olive oil.