In my mind this makes enough for 8 slices, though Kyle disagrees. He says one hungry teenager and the crumbs for his little sister (if she is lucky).
You will be able to tell when the condensed milk is okay as it will have gone a shade of brown.
The can of condensed milk will be very hot so please wait about 30-45 minutes for it to cool.
Many use fresh cream on top as we prefer Greek yoghurt.
Time to cool usually takes between 1-2 hours depending on fridge temperature and temperature of your pie. But we get the best results by doing it overnight for the day after.