London's fire brigades are busy and there are several types of fire that happen more often than they should. One of those is kitchen fires some of which are caused when cooking is left unattended. It's easy to do that when so many devices these days have timers built in but, London Fire Brigade says "You should never leave cooking unattended – if you have to leave the room or the house, make sure to turn the heat off before you do.”
It's issued a list of safety measures that are applicable no matter where you live (except, of course, to change to emergency number to that of your country)