I stepped away from some simmering apple cider, and when I came back it was to smoke and popping noises! Oops, what a terrible mistake. I managed to clean all the carbon off with baking soda, but with it came a layer of the enamel from my 40+ year old pot. The bottom surface is no longer smooth, but there's no metal showing through. Is there anything I can do so I can still use this much-loved saucepan?