Cooking with Cast Iron: a Tex-Mex Chef’s Secret Weapon

Picture this: you’re at your favorite Tex-Mex restaurant, trying to figure out what you want to eat…and suddenly, a server walks by with a plate of sizzling, perfectly grilled fajitas. The sound and scent create a veritable siren song that grabs your attention and refuses to let go. When the server sets the plate down in front of someone at a nearby table, you notice that the fajitas are resting on a tiny, searing-hot skillet. “Be careful, the plate is very hot!” the server says. And as you watch your neighbor dig into their food, you start to wonder if you should order fajitas, too.

This scenario (and others like it) was brought to you by cast iron cooking, which is fairly common in Tex-Mex cuisine. Cooking with vessels made out of cast iron can be the secret to pulling off amazingly seared (and piping-hot, wonderfully aromatic) food at home, and a lot of people also love cast iron for its vintage look and feel. However, cast iron can be tough to work with if you don’t know what you’re getting into. Here are a few tips for getting started: 

Season Well

“Well, duh!” you might be saying to yourself. “Of course you have to season food while you’re cooking it! What difference does the pan make in that regard?” But actually, we’re not talking about seasoning food—we’re talking about seasoning the pan itself.

To season a cast iron pan is to introduce oil (flaxseed oil and canola oil are popular choices, as are lard and shortening) onto its surface and then subject the pan to high heat. When done correctly, this causes the oil to physically bond with the pan, creating a smooth coating that will help protect the pan from rusting and prevent food from sticking.

The idea of having to season the pan can be intimidating, but it’s really not too difficult. One popular technique is to preheat an oven to 350°F, brush a thin layer of oil all over your pan, use a paper towel to buff away the excess, and place it upside-down on the oven’s center rack. Bake the pan for an hour, then turn off the oven and let the pan cool for two hours. Repeat the process two or three times.

Every time you cook with some kind of oil or fat in the pan, the seasoning will get a little bit denser and stronger. The pan will also develop a darker color over time. You may have to do a manual re-season once in a while, but for many folks, simply using their pan frequently is enough to keep it in fighting shape!

It’s worth mentioning that a large number of cast iron pans sold nowadays are advertised as being “pre-seasoned.” This suggests that it’s not necessary to season the pan before you use it for the first time. However, most cast iron connoisseurs will recommend that you ignore this claim and season the pan, anyway. While the initial, “commercial” coat is good for keeping rust at bay (at least for a while), it’s not meant to be a permanent solution.

Know Your Pan

Contrary to popular belief, cast iron is not valued for its ability to heat evenly in all directions. If you put a cast iron pan on the stovetop and simply leave it be, it will develop hot spots in the shape of the burner. Unlike aluminum or copper pans, which typically warm up evenly on their own, cast iron pans need to be rotated (or at least wiggled around) regularly to allow heat to spread throughout the vessel. This property is also why it’s important to allow the pan to preheat (preferably in the oven) before you start cooking.

What cast iron pans do have is a major knack for maintaining heat. Once you get your pan nice and hot, it’s going to stay that way for quite a while. It can also withstand very high temperatures without warping or weakening. Thus, it’s great for searing meat and other foods at a high, steady temperature. Cast iron is often the trick for making those incredible fajitas that so many Tex-Mex restaurants are famous for; you can even get cast iron plates on which to serve the food! Just be sure to not touch the plate/pan when it’s hot, as a serious burn on your hands or arms can very easily ruin your night. 

Wash Carefully

The proper technique for washing cast iron pans is pretty hotly debated in the culinary world, and the argument essentially comes down to whether you’re a soaper or a no-soaper.

As their name implies, “no-soapers” believe that you shouldn’t use soap when washing a cast iron pan. Their thought process is that soap can remove the seasoning on the pan, thus making it harder to use and clean as time goes on. So, if you ask a no-soaper to wash your pan (or any other cast iron object), they’ll simply scour it vigorously with a sponge or dishwashing brush and hot water. If there are stubborn spots that won’t scrub clean, a paste made from kosher salt and water can be used as a seasoning-safe abrasive.

Meanwhile, “soapers” argue that using dish soap is a great way to save time and energy on pan maintenance; a little bit of dish soap isn’t going to do any real harm. If the pan is seasoned properly, it’ll actually take something like lye or other extraordinary measures to remove the protective coating—and, worst case scenario, you can always season the pan again. If you ask a soaper to wash your cast iron vessels, they’ll probably grab a sudsy sponge and treat them like any other cooking utensils.

For what it’s worth, science is on the side of the soapers. Due to the chemical properties of heated oil and iron, dish soap isn’t likely to wreck a pan’s seasoning unless it’s introduced via steel wool (or an equally abrasive substance). But people who regularly cook with cast iron tend to feel very strongly one way or the other, and both techniques are valid. Our advice: do what works for you, and when you’re in someone else’s house, defer to their preferences. Otherwise, you might find yourself banned from their kitchen for life!

There’s one thing that soapers and no-soapers can agree on, though: be wary of water. Don’t soak the pan in water for an extended period of time, don’t put it in the dishwasher, and don’t let it drip-dry after being washed. Why? Because leaving the pan wet for an extended period of time is a surefire recipe for rust! So always take the time to dry it completely after a cleaning. Some folks use a heated oven for this, just to be absolutely certain that their pan is moisture-free!

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You’d probably be hard-pressed to find a person who truly, genuinely believes that cooking with cast iron is “easier” than using aluminum pans coated with Teflon. The pros may make it look easy, but in truth, cast iron must be prepped, used, and maintained properly in order to yield great results. We strongly encourage you to step outside your comfort zone and try cast iron cooking if you feel up to the challenge. Just don’t get cocky, lest you watch your dreams of picture-perfect fajitas—quite literally—go up in smoke!