Like all tacos, fish tacos are a form of comfort food. But unlike mac and cheese or mashed potatoes, fish tacos are the only comfort food that make you feel like you're at the beach.
Maybe that's because you were at the beach the first time you had them, but suppose you want to make your own fish tacos at home. Most recipes for fish tacos say something along the lines of "use any mild-flavored, lean, flaky, white fish, like cod, haddock or tilapia." And this is helpful up to a point. But what is the absolute best fish to use for making fish tacos? The answer depends on what kind of fish tacos you're making.
Fried Fish Tacos
In large part, it depends on how you're preparing your fish. If you're making traditional Baja California-style fish tacos, you're going to batter and fry the fish before wrapping it in a corn tortilla along with various crunchy, creamy, and spicy ingredients.
Baja-style tacos are usually made with cod or tilapia. The fish you use needs to be firm enough to fry well, and mild enough so that it is essentially a blank palate upon which the other flavors perform their alchemy.
Lean fish are also the best for deep frying. Fatty fish like tuna or salmon can taste too oily when cooked in the deep-fryer. For the traditional-style fish taco, stick with cod or tilapia. Other choices include pollock, haddock, striped bass, snapper, and catfish. Catfish is actually an excellent choice as it is excellent fried.
Grilled Fish Tacos
Fried fish isn't the only way to enjoy fish tacos. For a different, healthier option, you can grill, pan-fry, or even steam the fish. Grilling is probably the best non-frying method for preparing your fish for fish tacos. It's a great way to get that extra robust flavor on your fish, not just by seasoning and marinating it, but also from the way it browns and crisps up on the grill.
For grilled fish tacos, you're looking for fish that holds up well over high heat. Again, cod and tilapia are good choices, but when grilling you can use fattier fish like tuna, salmon, and swordfish. Halibut isn't technically an oily fish, but it's a "steaky" fish as opposed to flaky, which means it's also a good choice for cooking on the grill.
Stick With Inexpensive Fish
Another issue is cost. Tacos are street food. When you think about the meats that are traditionally used for making tacos, it's always the cheaper cuts which are either braised to make them tender, like carnitas, or grilled and then chopped finely, like carne asada. Other traditional taco meats include cabeza, or the meat from the cow's head, lengua, the cow's tongue, and sesos, the brains. Buche is another common taco meat which is made from the braised stomach of a pig.
The point is, no one makes tacos from beef tenderloin. Likewise, you should not make fish tacos from the most expensive fish. For one thing, the fish itself is not the central flavor of the taco. Traditional fish tacos are made with mild-flavored fish and what you're really tasting are the toppings, which include strong flavors like chiles, raw onions, citrusy mayonnaise, and lime juice, as well as the flavorful batter that the fish is fried in. So it stands to reason that you'd stick to cheaper white fish like cod and tilapia as opposed to something more expensive, like halibut or sole.
And don't turn up your nose at frozen fish. In many cases, fish is frozen right on the fishing boat and it stays that way all the way to the market, so it is almost certainly fresher than the "fresh" fish you buy at the grocery store which was likely previously frozen and then thawed.
Fish to Avoid for Tacos
The types of fish to avoid will depend on if you're frying or grilling your fish. Flaky white fish like cod, tilapia, and catfish are best for frying, while salmon, tuna, and halibut are good for grilling. Avoid super flaky fishes when grilling if you want your fish to come off the grill in one piece, and avoid frying oily fish like salmon and tuna. Almost any type of fish will work for fish tacos depending on how you prepare it.