Remove the label and the label adhesive from the can of sweetened condensed milk. This is necessary to prevent any paper or adhesive from potentially gumming up the pressure cooker's release valve.
Place the can in a pressure cooker and cover with water, to a minimum of 2 fingers over the can.
Seal the pressure cooker and turn it to pressure mode.
Place on a burner over medium heat and cook until the pan starts to hiss, indicating the buildup of pressure.
Once the hissing starts, set a timer for 20 minutes.
When the 20 minutes are up, turn off the burner and turn the release valve to allow the pressure and steam to escape the pan.
When the pressure has been released, open the pressure cooker and, using a set of tongs or a canning lifter, lift the can out of the pan.
DO NOT OPEN THE CAN UNTIL IT IS COMPLETELY COOLED. The milk caramel will be liquid and very hot. This creates pressure in the can. If it is not completely cooled, the contents of the can could spray and potentially cause burns, not to mention make quite a mess. I cool mine in a sink full of cold water.
Open the can after it has cooled and transfer the milk caramel to a glass container with a lid for storage.
Use as a spread over bread or fruits (such as apples or bananas).