I did something really stupid, and walked away from a sugar solution I was heating on the stove (4 parts water, 1 part table sugar for humming bird feeders). I got distracted, and the sugar was burnt onto the pan, carbonized, really bad. Some came off in chunks, but a thick layer adhered to the stainless steel pan. I had a cover on the pot at the time, I assume the lack of oxygen kept it from flaming? The web had many recommendations for baking soda and water at a simmer. I was skeptical, but figured I had little to lose, baking soda is cheap and pretty safe. Almost no effect, even though I gave it a couple tries and left it simmer for 20 minutes or more. Then I see recommendations for Hydrogen Peroxide. OK, that sounds a little riskier, but not too dangerous. I was skeptical at this point, but I added ~ 1/4" of the generic 3% stuff to the pot, and as it reached a simmer, about half of it lifted right off. Alright! Another 5 minutes of simmering and swirling and ~ 99% was off, and little wiping removed the rest. Looked like new. I assume the people reporting success with the baking soda merely had a thick, cooked, hard syrup that would still react with water? What I had was carbon, charcoal like stuff (yes, there was a lot of smoke, and two alarms were beeping - it was bad). I'm not well versed in chemistry, any simple explanation of what happened with Hydrogen Peroxide, heat and carbonized sugar?