-Heavy Cream -Vinegar
Add the cream to a mason jar or other airtight container.
Add the vinegar (or lemon juice) to the cream.
Close the container and shake it for a minute or two until the cream thickens.
Use the cream right away or leave the jar (with the mouth covered in cheesecloth or other lightweight cloth and secured with a rubberband) on your counter overnight to ferment and thicken.