1 carton (125g) of natural yogurt (any brand from the local grocer will do)
1 litre of milk (full cream or low-fat milk)
1. Bring the milk to boiling point. Then pour into a non-metal container (like a heat-resistant plastic container or glass jar)
2. Let the milk cool until lukewarm, when a layer of skin will form on top
3. In a separate bowl, mix three tablespoons of natural yogurt (any brand from the local grocer will do) with three tablespoons of cold milk. Stir the mixture well
4. Add the mixed yogurt to the lukewarm milk. Carefully pour the yogurt down the side of the container so as to not spoil the skin on top of the milk
5. Cover with a clean dishtowel or the lid of your container and place in a bigger container such as a stockpot for between eight and 12 hours until it thickens. I sometimes leave it overnight too
6. Store in the refrigerator and use within five days.