Wall Oven and Ranges - Cooking Too Slow or Too Fast
If the oven is cooking too slow or too fast, the oven thermostat may need to be adjusted (calibrated).
If you have a new oven or range, the oven has been set correctly at the factory and is more apt to be accurate than the oven which it replaced. When using recipes you've used for a long time, differences in timing or cooking performance between an old and a new oven are not unusual. For the first few uses, follow your recipe times and temperatures carefully and use the rack positions recommended in the Cooking Guide in your manual.
If you still think your new oven is too hot or too hot or too cold, you can adjust the temperature yourself to meet your specific cooking preference. You can also adjust your thermostat if your oven is not new, since thermostats may "drift" from the factory setting over time. See the "Adjust the Oven Thermostat" "Do It Yourself" section of your Owner's Manual.
Make 1 adjustment and then use the oven 3 to 5 times before making a second adjustment (if necessary).
After adjusting, you might test the oven temperature for accuracy with biscuits or cookies which have specific instructions. You can easily test to see if your oven is cooking properly using the "biscuit test". For more information, visit: Oven Temperature Bake Test.