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How to Preheat an Oven – All You Need to Know

how to preheat an oven

Whether you’re baking a pie, roasting some vegetables or cooking a lasagna, most oven recipes require that you preheat the appliance. It’s an essential step to ensure that your meals are put in the oven at exactly the right time and come out just the way they should. Nothing is more disappointing than finding that your food is undercooked or burnt. Here’s what you need to know about preheating your oven.

Why preheat the oven?

Preheating the oven matters. When you switch on the oven it will gradually heat up—climbing from room temperature all the way to the set heat. While this process can take between 10 to 15 minutes (which can feel like an eternity), it’s important to preheat your oven  because most recipes are based on dishes being cooked at a set temperature.

Generally, baked goods with eggs and flour and dishes that cook quickly should definitely be put in a preheated oven. If you put in a dish too early—while the oven is still preheating—and follow the recipe, chances are that after the recommended time in the oven it won’t be cooked properly. Then you’re left to improvise and wait around to monitor when it’s done. This means you could run the risk of undercooking or burning your food.

More fragile baked goods like cakes or croissants can be completely ruined if they’re under- or overdone.

How to preheat the oven?

Usually, you don’t have to turn on the oven right away (when you’re still preparing the food). If you’re following a recipe, it will usually tell you when to turn on the preheat.

If you need to prep a lot of ingredients before you can begin to cook a meal, as is the case for more complex oven dishes like lasagna, you won’t need to turn the oven on until 10 to 15 minutes before you’re ready to get cooking or baking. Simpler dishes like pizza may not always need preheating, but it’s best to check the recipe.

So how do you know when the oven is preheated correctly? Some ovens have digital controls. Simply check the screen to see if it has reached the desired temperature. Traditional gas oven models tend to go idle when they reach the right temperature, and they’ll go noticeably silent.

How long does an oven take to preheat?

A good rule of thumb is: convection or fan ovens tend to heat up much faster, so you’ll only need to wait 10 minutes to start preheating. Standard gas ovens are a little slower and should be preheated 15 to 20 minutes before you add a dish for cooking.

To get the temperature perfect, you could invest in an oven thermometer. They’re available from most home appliance stores and online to help ensure that every meal comes out just right. No more burning!

There’s not usually any danger from preheating an oven too long, other than wasting energy. The oven will just continue to turn on and off to maintain your set temperature.
While following a recipe is generally recommended to ensure your dishes cook or bake the way you want them to, you should always follow your nose, taste buds, and eyes when cooking to make sure your dish turns out just right.