I’ve been a rule-follower from way back. Just ask my family or my co-workers or, well, anyone who has interacted with me on even a superficial level. But some things are more guidelines than actual rules.
For example, one of the more common inquiries we get from like-minded conscientious readers is whether it’s OK to use cast-iron cookware on their glass-ceramic cooktops, whether that’s traditional electric (radiant) or induction. If you stuck to the letter of the law from what some manufacturers say or have said in the past, the answer would be no. And if I listened to that advice, I’d never use some of my best, most-reliable pots and pans on my range at home.
Generally, though, “it’s fine,” says Lisa McManus, executive editor of reviews at America’s Test Kitchen. Manufacturers who recommend against using cast iron are likely covering themselves in the event that consumers damage the glass with improper usage and call for repairs or replacements while the cooktop is under warranty, McManus says.
Often, the message is one of caution rather than discouragement. “Cast iron can be used on any smooth-top/glass surface range or cooktop,” according to Whirlpool’s Pat Duffy, product marketing manager, and Katie Sadler, kitchen brand manager. That’s assuming you take a few small steps to be careful.
Here’s a quick rundown of what you should and shouldn’t do.
Don’t drag cast-iron cookware across a glass surface. “A lot of cast iron is rough on the bottom,” McManus says. Dragging it can result in scratches. You run less risk from enameled cast iron than traditional uncoated cast iron. Either way, when placing cookware on or removing it from a burner, make the effort to lift instead of slide it.
Whether from cast iron or other daily use, you will likely end up with small shallow scratches, even if you’re careful — I certainly have. In that event, don’t sweat it. “Small scratches do not compromise cooktop functionality on either induction or radiant cooking surfaces,” the Whirlpool reps say.
Don’t drop cast-iron cookware on the cooktop. Anyone who has used cast iron knows how heavy it can be. So if you drop it on glass, it can certainly cause breakage. Keep in mind that the glass itself is not functional, McManus says. In the case of radiant electric cooktops, the glass-ceramic covers the kind of electric coil burner you may recognize from older ranges. In induction cooking, the surface covers copper coils through which run alternating electric currents, creating a magnetic field, the reason only certain cookware — cast iron included — is compatible with these types of ranges.
Do modify the way you cook. If you’re someone who likes to shimmy and shake the pan as you cook, you’ll want to try a different technique with cast iron on glass-ceramic. That kind of movement can cause the scratches described above. Instead, focus on moving the food around the pan with a utensil, such as a spoon or spatula.
Cast iron’s excellent heat retention also means you may need to account for it taking longer to heat up and cool down. If a recipe calls for searing or bringing something up to a boil before reducing the heat, you may want to turn down the temperature a little sooner to account for the residual heat in the pan, especially if you’re trying to avoid burning or a boil-over. Another option: Switch burners — remember, lift, don’t slide! — so you can immediately put the food on a lower heat setting.
Do keep your cast-iron cookware clean. Especially with a dark pan used for high-heat cooking, it can be easy to miss charred bits of food or drips down the side. That can prove problematic on a smooth cooktop, where the food or residue can burn, making cleaning the glass more difficult, Whirlpool says. And if you’re seasoning your cast iron, as you should, make sure not to leave excess oil on the exterior, which can also burn.
Don’t be afraid. As fans know, cast iron is durable, efficient and affordable. McManus says the small amount of extra care you have to take when using cast iron on smooth cooktops is well worth the benefits you reap: “Don’t skip using this fantastic type of cookware.”