I have always regarded the darkening of baking pans to be a good thing… good in the same way that darkened cast iron and woks is “seasoning.” Indeed, at times when we have replaced our darkened baking pans with new shiny ones (such as a yard-sale find), we found that shiny is not always better.
For example, the bottom of our pizza didn’t brown as nicely in the new shiny pan. Cookies spread too much on new shiny cookie sheets. I have also read that dark pie tins are better for pie crust, as shiny pie tins reflect too much heat for the bottom of the crust to bake well.
So I never gave much thought to my darkened cake pans. I always scrubbed the inside clean, but let the outsides get dark over time. Recently I had a new box of Brillo pads, and was inspired to see if I could get the outsides of my round cake pans shiny. I did one, decided it was too much work, and left the second one dark.
As a result, I accidentally did a double-blind study. When I subsequently baked cakes in these pans I was shocked to see how much difference there was in the way these to cakes baked. The cake in the shiny pan had almost no darkened bottom or side crusts, and it rose more. The cake in the dark pan had a thicker outside crust, rose less so was more dense, and burned slightly on the bottom. I have always removed the cakes as soon as they they passed the clean-toothpick test. Now I know why the outsides of my cakes got too dark before the inside was fully cooked.
I did a little internet research and indeed found that Martha Stewart advises baking cake in shiny pans for the reasons I found.
I will be scrubbing that second pan until it is shiny.
Homepage photo credit: katalicia1