1 cup (8 oz or 237 ml) heavy whipping cream – here in the US there is whipping cream and heavy whipping cream, get the heavy kind, the one with the highest fat content
1/4 cup (59 ml) milk
3/4 tsp white vinegar
In a small bowl, add the milk and the vinegar stir, and let stand for 10 minutes. Wait until it curdles.
Add the heavy cream into a pre cleaned and sterilized jar, whisk in the milk mixture. Cover the jar and let stand at room temperature for 24 hours.
When 24 hours has passed, transfer it in the fridge. Use within a week.
Adapted from All Recipes