Built-in electric oven with an open door
Why It's Important To Preheat An Electric Oven Longer Than A Gas One
There can be a pretty big difference in the amount of time it takes to preheat an oven if you're comparing an electric oven to a gas oven.
Electric ovens require longer preheating times compared to gas because they rely on heating coils that need time to heat up.
Alternatively, gas ovens use burners that offer almost instant heat when ignited. Thus, an electric oven can often take twice as long to preheat than a gas oven.
Oven dials are often inaccurate, so instead, use an oven thermometer to get an exact read on the temperature inside the oven by placing it on the rack.
Be sure to wait 15 to 20 minutes to preheat your oven fully. This is important because skipping preheating often leads to uneven or undercooked dishes.
The USDA even warns about avoiding the "danger zone," which falls between 40-140º F. At this temperature, harmful microbes multiply rapidly, so don't skip the preheating step.