01 - Pour the milk into a saucepan and set over medium heat. Stir occasionally and warm the milk until it reaches 185°F (85°C). Do not allow the milk to come to a boil.
02 - Remove the saucepan from the heat and let the milk cool to between 110°F and 113°F (43–45°C). Use a kitchen thermometer to monitor the temperature accurately.
03 - In a small bowl, combine the yogurt starter with a few tablespoons of the cooled milk. Whisk until the mixture is completely smooth and free of lumps.
04 - Pour the starter mixture back into the saucepan with the remaining cooled milk. Stir thoroughly to ensure even distribution of the live cultures.
05 - Pour the inoculated milk into a clean container or divide among individual jars. Cover loosely with lids or a clean towel.
06 - Place the containers in a warm, draft-free spot to incubate for 8 to 12 hours. A turned-off oven with the interior light switched on or a dedicated yogurt maker works well. The yogurt is ready when it has set to your preferred consistency and tanginess.
07 - Transfer the yogurt to the refrigerator and chill for at least 2 hours before serving. The yogurt will continue to firm as it cools. Store refrigerated for up to 1 week.