You might not lie awake at night wondering whether you should be baking atop the shiny side or the dull side of aluminum foil, but just in case you are, we're here to let you know that there is indeed an answer to this eternal mystery.

According to Reynold's Kitchen, the difference in appearance between the two sides of aluminum foil is simply a result of manufacturing and serves no real purpose. Meaning, whether you are cooking your food with the shiny side up or the dull side up, you're doing it right.

On Reynold's FAQ page, the company gets into the nitty gritty over why one side is shiny and one is dull:

"This is a common question and the answer is that the foil is "milled" in layers during production. Milling is a process whereby heat and tension is applied to stretch the foil to the desired thickness. We mill two layers in contact with each other at the same time, because if we didn't, the foil would break during the milling process. Where the foil is in contact with another layer, that's the "dull" side. The "shiny" side is the side milled without being in contact with another sheet of metal. The performance of the foil is the same, whichever side you use."

One quick caveat though: If you are using non-stick foil, you definitely want to make sure to use the dull side, since only one side has the non-stick coating applied. Thankfully, Reynolds has spelled it out for us by imprinting the words "NON-STICK SIDE" onto, obviously, the side with the non-stick coating.

So there you have it: Now you'll never be foiled by aluminum baking sheets ever again. (Sorry, we had to.)

(h/t Huffington Post)

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Katelyn Lunders
Deputy Digital Editor

Katelyn Lunders is the Deputy Digital Editor of House Beautiful, where she oversees the brand's digital strategy and audience growth. When she's not obsessing over the latest trend on TikTok, you can find her binge-watching house tours or online shopping for her Upper East Side apartment.