Greek Yogurt (Yiaourti)
Bring 1 litre (2-1/4 pints) of whole full-fat milk to just under boiling point and then pour the milk into a glass or earthenware dish. Let the milk cool to about 42°C/104°F.
Mix 2 to 3 tablespoons of commercial plain yogurt or from a previous home-made yohurt (at room temperature) with a few tablespoons of milk, and pour into the milk carefully without disturbing the skin that may have formed on the surface of the milk. Cover with a cloth, place in a warm, draft-free place for 8 to 12 hours or overnight, and do not disturb it until the yogurt thickens.
Drain any excess liquid and store in the fridge for 4 to 5 days.
To make a "thick" yoghurt, remove the skin on the surface of the yoghurt just made and pour the yoghurt into a muslin bag. Hang the bag over a bowl and let drain for about 2 hours or until the desired thickness is obtained.