Place water into the slow cooker and turn onto low heat.
Remove the labels from the cans.
With a permanent maker, label the cans and date them with the date you made caramel.
Place the cans into the slow cooker and make sure the water is over the top of the cans.
Let the slow cooker cook on low for at least 8 hours, checking to make sure the water is love the cans.
Remove the cans and place them on a towel on the counter. Allow them too cool. You can then store the homemade caramel sauce for a few months before eating.
Video
Notes
You can put the sweetened condensed milk into sterile half pint jars with seals and bands, processing as above for 8 hours. The caramels shelf life is 2 months.