Pour the Sweetened Condensed Milk evenly into three Mason Jars.
Place on the lids and tighten.
Pressure Cooker
Add a Trivet to the Pressure Cooker cooking pot. Place Jars on Trivet. Fill Pressure Cooker with water to 1/2 inch below the rim of the Jars.
Lock on Lid and close Pressure Valve.
Cook at High Pressure for 40 minutes.
When Beep sounds, allow a full Natural Pressure Release.
Carefully remove jars to a cooling rack. Remove rings and after 15 minutes, remove lid and stir. Place lid back on and leave undisturbed, until cool. Transfer to the refrigerator.
Slow Cooker
Place jars in Slow Cooker and fill with water to at least one inch above the jars.
Cook on LOW for 9-11 hours, checking at 9 hours to see if the color is to your preference.
Carefully remove the jars from the Slow Cooker to a cooling rack. Remove the rings. Leave undisturbed, until cool. Transfer to the refrigerator.
Notes
With this Simple Dulce de Leche Recipe, you can decide the level of depth and darkness that you want your Dulce de Leche. I like mine dark, so I cook for 11 hours. Some people prefer a lighter Ducle de Leche and cook for 9 hours. Check your Jars after 9 hours to see if your Dulce de Leche is the color you like. If you want a darker color, put them back into the Slow Cooker. For the smaller Ball 4 oz Mason Jars, 9 hours is pretty good.