Silicone baking mats are a terrific alternative to parchment paper. Pop the mat into a rimmed baking sheet, and you instantly have a nonstick baking (or even roasting) surface that you can use, wash, and reuse. (Our winner, the Demarle Silpat Silicone Cookie Baking Mat, is ovensafe up to 500 degrees.)
But over time, these mats can build up a sticky—and often stinky—residue of polymerized fats that no amount of scrubbing will remove. To find a remedy, we followed suggestions we found online, including soaking the sticky mats in solutions made with vinegar, lemon juice, baking soda, and hydrogen peroxide. The only successful method was placing the mat in a hot oven.
We found that leaving the mat in the oven for a full hour made it significantly easier to remove the residue with soap and water. That's because heat not only broke down the fat but also disrupted the bond between the residue and the silicone. In addition, heating longer and hotter helped break down and burn off sticky, partially polymerized fats.
How To Do It:
Note: This method will not remove the brown spots that these mats acquire over time.