Remove the label from the can and clean off as much of the glue as possible. (This is optional, but the glue can leave behind a sticky residue on the inside of your crock pot. Use some goo gone if you’ve got it.)
Lay the can on its side in the bowl of your crock pot. Fill the crock pot with water until it covers the can by two inches.
Set your crock pot to low and cook for 8-10 hours (the longer it cooks, the darker the dulce de leche will be).
Remove can of milk and let cool for about an hour before opening, or until it reaches room temperature.
Refrigerate after opening. Dulce de leche will keep for about three weeks in the fridge.
