I only use the microwave to reheat food, so haven't burnt anything in the microwave!
On the other hand..... I have burnt some puff pastry in the oven before. I had some frozen puff pastry in between two baking trays (trying to crisp it up) and I didn't know how long to bake it for, so just let it in there until I can smell it.... 'burning'!! To my horror the whole thing was black when I took it out of the oven. haha that went into the bin of course,
I made a pavlova that turned out like the apparition in the photo . . . and the smell was, well, there are no words. Turns out the thermostat was fritzed. Boy, did I have fun trying to scrape that baby off the pan!!
Only on top of the stove. About 38 years ago I burnt some food, couldn't put the little fire out, so I had to,rang the fireman & I asked not to put the siren on when they came to the house, but they did anyway No damage done! Recently I had a saucepan on the hot plate, with the lid turned upside down in it. When the fire alarm went off, I was looking at a story on the tv! Ops! I burnt the saucepan,& the plastic handle of the lid. The awful burnt plastic smell lasted 3 days! I can still use the saucepan & the lid though. .