Fudged up

A total culinary disaster today.
My mother is a fudge expert and has never lost a batch. I however have made it once before fairly successfully and thought the second time would be as easy.
Not so. It went black and filled the entire house with burning sugar smoke. I poured out half into a tray in some vain hope it would be ok and threw the rest in the sink. The stuff in the stray hardened to black glass and the stuff in the sink welded itself to every surface it touched and it took me two hours furious chipping and scrubbing to resurrect the pans. In fact I was still clearing up when the wife got back from Russia