If you have ever followed a recipe, especially for baking, only to find out you have burned your goodies, you will love this tip!
For under $10, you can get an oven thermometer like this one. Place it in a cold oven (best on the middle rack that you would most often bake on) and turn your oven on to 350. If you have a “preheating” button or light that stays on until the oven is the proper temperature, just look at the thermometer when the oven is ready and see if the temperature reading on the thermometer is what it should be. If you don’t have one of those lights, wait for about 20 minutes and then test the temperature.
Most ovens are off by a few degrees (which is usually fine for home cooks). But if you find it is off by 10-15 degrees, just adjust your cooking time accordingly. This is the cheapest way to calibrate your oven (if you get it done professionally, it will cost quite a bit!). Once you know what the ACTUAL temperature is in your oven, you can either increase your cooking time if it is low, or check your baking before the suggested cooking time in a recipe to avoid over-cooking.