Last night I made sweet potato fries as I have on many occasion. I slipped them in at 400 degree's for 20 minutes. They were cooked through but I wanted some of the brown sugar to caramelise so I turned off the bake and turned on the broiler...........and then completely forgot about it. My mind came back to task when smoke started coming out the vent under one of the elements. They were CHARD BLACK. I also ruined my dollar store barely more than tin foil single use pan which I've washed and reused several times. So sad.