The Food Lab: Better Home Cooking Through Science

As far as retaining heat goes, nothing beats a good cast-
iron pan. Its specific heat capacity is lower than of
aluminum, but because it is so dense, for the same thickness
of pan, you get about twice the heat retention capability.
This is important: the pan doesn’t cool down when you add
food to it. While the temperature in a thin aluminum pan
may drop by as much as 300 degrees when you add a half-
pound rib-eye steak to it, a cast-iron pan will stay close to its
original temperature, delivering a thicker, crisper, more
evenly browned crust. Similarly, you can get away with
using a little less oil when frying chicken, since the heat
retained by the cast iron will rapidly reheat the oil when the
chicken you add cools it down.
The fact that cast iron is oven-safe means that you can
braise and bake in it just as well as you can fry or sear. Corn
bread comes out with a beautiful golden brown crust, and
pies, even with moist fillings, come out wonderfully crisp on
the bottom. Its heat retention abilities mean that even when
your oven’s temperature fluctuates (as most thermostat-
driven ovens do), the pan’s heat will stay fairly constant.
And talk about durability! Cast-iron cookware is one of
the few items in your kitchen that actually gets better as it
gets older. Some of the very best pans have been passed
down through multiple generations, their well-used surfaces
worn as smooth and nonstick as a Teflon-coated pan—
without the toxic chemicals. And because cast-iron pans are
cast from a mold as a single piece of metal, there are no
welded joints or even rivets to wear out.
There are, of course, a few downsides to cast iron: