When I first moved into my apartment, I decided to christen my new oven by baking my favourite chocolate chip cookies. I’d made this recipe almost weekly at my old place, so I was pretty much an expert by this point. So when they came out of the new oven as undercooked dough balls, I was confused. I tried the recipe again, with the exact same result. I turned to the Internet for advice.
That’s when I first learned ovens can vary in temperature. Luckily, there’s a simple and inexpensive solution to this common problem: an oven thermometer.
I know, your oven has a built-in thermometer — why would you need to buy another? Well, ovens lie: They have this nasty habit of saying they’re at a specific temperature when they’re actually significantly under or over it. A temperature off by just 25 degrees F can affect your baked goods. When I found out my oven was actually at 260F, when it said it was preheated to 350F, I was in shock. No wonder my cookies changed in texture, spread and bake time.
I actually have two thermometers in my oven, one at the top and one at the bottom, in order to ensure consistent baking throughout. (This oven thermometer is available on Amazon for under $10.) Moving your thermometer around is a simple way to determine where your hot spots are. Since purchasing my thermometer, my bake times and results have been noticeably more consistent.
Once you have an oven thermometer, test your oven by preheating it to a specific temperature. Once it’s preheated, give your thermometer a read and record the results. Carefully move it around to different areas of your oven to check for hot spots. You’ll soon be able to determine whether or not you need to rotate your dishes while they’re cooking and if you should to set your oven over or under the temperature a recipe recommends.
Becoming informed about your oven’s is a huge step towards delivering perfect cookies every, single time. Because maybe, when it comes to cooking mishaps, it’s not you — it’s your oven.
Watch: How to make easy chocolate cake
Published May 2018; updated November 2021