Fried Fish Sandwiches Are 10x Crunchier When You Add These 3 Ingredients To The Batter

Close your eyes and think of the perfect fried fish sandwich — it's probably covered in tartar sauce, with a crust so crunchy that it shatters when you bite into it. You might also be picturing yourself sitting in a restaurant in order to enjoy it, right? Well, here's some good news: You can easily whip up this crispy fish dish at home if you mix together the right batter. Specifically, one that contains rice flour, cornstarch, and baking powder because together, these three ingredients do wonders in creating a lighter, more porous, crispy crust.

First, let's talk about rice flour. It differs from standard wheat flour in that it doesn't contain gluten, which means it doesn't yield the same stretchiness when mixed with water. And this small fact matters when creating a crispy fried coating — too much gluten can produce a tougher, almost chewier batter instead. Research on fried batters in journals like Bioscience, Biotechnology, and Biochemistry has found a link between rice flour and crispiness, which is why rice flour makes such a brilliant addition to crispy fried chicken too.

Then, throwing cornstarch into the mix ramps this up a bit. Made entirely of starch and devoid of protein, cornstarch helps create a thin and brittle crust. And finally, we add baking powder, which has a different role altogether. In hot oil, it releases gas, which creates little pockets in the batter rather than letting it become one dense layer.

This batter combination really starts to pay off the moment you start frying. As the fish hits the hot oil, moisture escapes the crust, leaving behind a drier, more porous structure. Rice flour and cornstarch work together to create a crisp, delicate structure, and the baking powder keeps it light and airy. The combination of lots of tiny pores and low moisture creates that final crunchiness, not to mention that unmistakable sound when biting into it, which actually helps our brains perceive crispiness in the first place. 

But this isn't about throwing as much of each of the three ingredients into batter and hoping for the best. There are proportions that very much matter in the quest for the perfect crispiness — too much starch can make a batter lean too brittle or fragile, for example. Following Chowhound's own beer-battered fish sandwich recipe, you can use roughly three parts rice flour to one part cornstarch, plus about a tablespoon of baking powder for four 5-ounce filets of fish. Then add in cold sparkling water or beer, keeping the mixture cold until you fry in oil heated to around 350 Fahrenheit to 375 Fahrenheit.

Once it's fried and golden, move it to a wire rack (not a plate), which lets steam escape properly without getting trapped beneath the fish and turning it soggy. Complete the meal with some of the best toppings for a fried fish sandwich, and you've got a real catch (if you'll excuse the pun) on your hands.