Might I just add, that I have a 30 year old slow cooker, (A corden bleu make, I don't know whether you can still get them) and it is like an original earthenware pot and no temperature control, only that it is either plugged in or it isn't! My instructions tell me to preheat the cooker, before adding foodstuff.
However, I was staying with my sister in Engand and was making a chilli, in her much more modern slow cooker. I preheated the device, brought the chilli up to the boil and poured it into the heated vessel. All I heard was a loud cracking noise. Unbekown to me, hers was a slow cooker that you did NOT reheat. Whoops! That made that a more expensive din[color=#8000BF]ner than anticipated.
Just saying, you don't always have to preheat them
However, I was staying with my sister in Engand and was making a chilli, in her much more modern slow cooker. I preheated the device, brought the chilli up to the boil and poured it into the heated vessel. All I heard was a loud cracking noise. Unbekown to me, hers was a slow cooker that you did NOT reheat. Whoops! That made that a more expensive din[color=#8000BF]ner than anticipated.
Just saying, you don't always have to preheat them