And it starts with something most people throw away.

I spent much of my childhood in my grandma’s kitchen. I was usually beside her at the counter, learning how to make pasta and bake fresh bread, absorbing the rules she lived by—like the fact that every dinner absolutely had to include one protein, one vegetable and one starch. No negotiations. Her set of vintage Pyrex mixing bowls is still my favorite thing in my kitchen, and I cook with them every single day. I lost her about 12 years ago, but some days in the kitchen—her bowls on my counter and her wedding band on my finger—I still catch myself using the tricks she taught me.

I noticed one of her habits very early on. Whenever she unwrapped a stick of butter, she wouldn’t crumple up the paper and toss it in the trash. She’d smooth it out and set it aside for later. Eventually, I realized why. When it came time, she’d grab one of those wrappers and run it across whatever she was baking or cooking with—cake tins, casserole dishes, cookie sheets. The paper always held just enough butter to grease the pan easily and evenly.

Because I saw her do this from a very young age, I assumed it was simply how cooking worked. Butter wrappers went in the fridge, not the garbage. It wasn’t until much later that I realized most people had never heard of saving them at all.

Why Butter Wrappers Are Perfect for Greasing Pans

A butter wrapper might not seem like it has enough butter on it to grease a whole cookie sheet, but there’s just enough for a light, even coating.

Using the wrapper makes it easy to reach the corners and sides of baking dishes without getting butter all over your hands. The waxed paper also gives you something to hold onto, so you can swipe the surface quickly and evenly. It’s incredibly efficient—even for the nooks and crannies of the most intricate bundt pan shapes. Best of all, it’s a small way to use something that would otherwise go straight into the trash.

How to Use Butter Wrappers for Greasing Pans

Using butter wrappers to grease pans couldn’t be easier. After you unwrap a stick of butter, just fold the paper loosely and save it instead of throwing it away. To keep them handy, I store mine in a small resealable plastic bag in the refrigerator. The cold keeps the butter fresh, and the bag prevents the wrappers from getting everything greasy. When it’s time to grease anything from a cookie sheet to a lasagna pan, I grab one from the bag, use it, then toss it in the trash.

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