Josey wrote:

"Ian Stirling" wrote in message

Do you own and have a license for a multimeter?

Tell me more, I have a meter and a dusty o-level electronics certificate :-)

My first step would be to open up the oven (switch cooker isolator switch
off, if you can turn it off at the consumer unit), and verify that power is
off.
Then, find some way of attaching the probes to indicate voltage across
the oven element - you probably want the far side of the wiring loom, where
it connects to the thermostat or controller board.
I'd prefer not to be holding onto probes in the guts of the thing while
turning it on.

Now, turn oven on, and see if the voltage stays on as it reaches 100C.
If it does, then the element (or the connectors to it - check) has failed,
and is going open circuit when it gets hot.
If not, then it's a fault in the thermostat/...

If it's the element, then there is nothing you can do other than replace.

If it's the thermostat, then it may be repairable if it's a contact going bad,
as you might be able to polish it and get it working again.