Many recipes call for preheating an oven to roast, bake or broil whatever you’re making to perfection. But unless you’re making baked goods like breads or pastries, preheating your oven before you begin cooking is just wasting energy. A few minutes before you’re ready to toss your casserole or other dish into the oven, turn it on. It’ll get hot enough to get the dish started, and you won’t be wasting so much energy waiting for your oven to get to the desired temperature.
ANDREWS MCMEEL SYNDICATION