This is how I make yogurt:
Step 1: Put 1 liter of milk mixed with 0.2 liter of Yogurt on a heating radiator at 11PM.
Step 2: Wake up at 7AM. Yogurt is ready.
Step 1: Put 1 liter of milk mixed with 0.2 liter of Yogurt on a heating radiator at 11PM.
Step 2: Wake up at 7AM. Yogurt is ready.
EDIT: Warning, I do not know how many times can you safely reuse the Yogurt. I've reused the 'same' Yogurt several times without any issue, but please do your research. Of course, I store it in the fridge.
1. Warm milk to 120°F in a pan with a spoon of yoghurt
2. Put in thermos flask 8 hours / overnight
3. Put in a jar and leave in the fridge until cool enough to enjoy