Pour a quart of yogurt into a white cotton or cheesecloth bag. Tie the bag and suspend it from the faucet over a sink overnight, until the contents are firm. This is labana, yogurt cheese.
Place 1 heaping T of labana in the palm of your hand, roll it into a ball and place on a tray. Allow to stand overnight.
Pack the balls into sterilized jars and cover with olive oil. Seal the jars, and the cheese will keep for an extended period of time. Serve them with a little of the oil.