In Spain, swordfish steaks are often excellent--juicy, tender, delicate in flavor. They are also common. You will see emperador a la plancha written on chalkboards outside little neighborhood restaurants all over the country. They are a standard main course of the menú del día.
There are three secrets to swordfish pan-grilled the Spanish way. The first, of course, is to start with good fresh swordfish. The second is to never overcook it. The third secret--often overlooked--is cutting the steaks thin--at half an inch or less. Thin steaks allow for quick cooking and perfect texture.
In the U.S. swordfish steaks are almost always cut too thick, often an inch or more.
Even if you start out with top-quality swordfish, even if you carefully avoid overcooking, a steak this thick is bound to come out dry and chewy. This is why swordfish in the U.S. is so often served with a fatty, tangy sauce or butter spiked with strong herbs--to disguise the flaws of poorly prepared fish.
Here in Central Florida, even at the best seafood markets, swordfish is usually displayed already cut into steaks--all of them way too thick. You could try to talk the person behind the counter into cutting a thin steak for you, but it's easier to do it yourself. Just slice the too-thick steak longways with a sharp knife.
The swordfish steaks are now 1/2 inch thick--perfect for emperador a la plancha.
Cooking the steaks is easy.
Just sprinkle the swordfish steaks with salt and pepper. Rub them with olive oil.
A heavy cast-iron skillet is best for pan grilling. I like to pan grill outside, on a propane burner, to avoid the smoke and splattered oil in the kitchen.
Heat the pan slowly (this helps to prevent sticking) until it is quite hot. Put in the steaks. It's not necessary to put oil in the pan. The oil on the fish is enough.
Cook the steaks two minutes on one side.
Now cook them two minutes on the other side.
That's four minutes total. Because the steaks are only half an inch thick, this is enough to cook them through. Be careful: don't overcook the swordfish or it will be dry.
That's it. The swordfish steaks are ready to serve. No spicy sauce or herbed butter necessary. They're perfect just as they are.