Combine milk, yogurt and vanilla (split and scrape the bean), gently stir using a whisk or spoon.
Pour into the jar/mini jars of your yogurt maker and let it thicken for 4/6 hours.
If you don't use a yogurt maker:
Heat the milk to 180°F (about 80°C), remove the pot from the heat and let it cool down to 115°F (approximately 45°C).
Pour the yogurt into a bowl of ceramic, add a bit of milk, stir and add the rest of the milk + vanilla and keep stirring to evenly distribute the yogurt.
Cover with plastic wrap and a cloth or a blanket, and put it into your oven with just the light on. Ideally, the oven should be at 85°F (30°C) - check with a thermometer.
Let it set for about 8-12 hours or until it thickens.
IMPORTANT: sometimes - depending on the temperature - the yogurt will be ready in just 4/6 hours, some other times in 8 or 12. Check the thickness every once in a while, and turn off yogurt maker (or oven) when it's ready.
Let it cool down at room temperature and then put it into the fridge: it will thicken even more!
Nutrition
Serving: 1serving (considering this recipe divided in 4) | Calories: 84kcal | Carbohydrates: 6g | Protein: 4g | Fat: 5g