Important: Every slow cooker is different. So the 1st time when you are using this method, keep an eye every hour or 2 hours ensuring that it doesn't stick to the bottom.
You can also lightly brush the inside of your slow cooker with oil before adding all the ingredients.
Sweetness: You can add 3/4 cup of condensed milk initially and then after 2 hours if the sweetness is not enough add the remaining 1/4 cup and stir.
You might have to take a note of the sweetness and slow cooker timings the 1st time.