You might think that a chef who was born and raised in Vermont, as I was, has as much business writing about tempura as a chef from Tokyo has writing about cheeseburgers. But any chef is bound to love the Japanese approach to cooking, an approach that puts a premium on using the freshest, best-quality ingredients and letting their natural flavors take center stage. Among Japanese cooking techniques, tempura is one of my favorites.
Tempura (the word refers to both the cooking method and the finished dish) is a wonderful frying technique that adds flavor and texture to food without competing with its natural flavor. Raw vegetables or seafood are dunked in a simple batter and then briefly fried in a mild-flavored oil, just long enough for the batter to crisp and the food to cook through. As the batter cooks, it forms a translucent coating that protects the tempura and prevents it from absorbing too much oil. Unlike some versions of batter-fried food, tempura tastes clean, fresh, and delicate.
As a technique, tempura is straightforward, and it also adapts well to American ingredients. If certain aspects of the technique don’t feel intuitive at first, particularly the slam-dunk method of battering and frying, don’t be discouraged. You’ll soon become proficient, and eventually tempura will become as valuable to your cooking repertoire as roasting or braising.
Search out seasonal vegetables and top-quality seafood
I make tempura all year long, but the vegetables I choose to fry change with the seasons. Finding exceptional ingredients is my priority, and that usually means sticking with seasonal food.
Vegetables with assertive flavors and a low water content work best for tempura. In summer, I turn to bell peppers, eggplant, green beans, and summer squashes like zucchini (with blossoms, if possible). I also dip fresh basil leaves in tempura batter (one side only) for a pretty garnish to a platter of summer vegetables. Cooler-weather vegetable candidates include carrots, sweet potatoes, and celery root. Sweet onions and fresh shiitake mushrooms are also wonderful for tempura.
In the seafood department, try shrimp and calamari tempura-style. I prefer white or pink shrimp from the Gulf or from Central or South America. They aren’t cheap, but their firmness and their clean, iodine-free taste make them worth the expense.
Cut the vegetables to sizes and shapes that let them cook at the same rate as the batter. Large vegetables should be cut into slices, thin strips, or chunks (see the chart for cutting techniques for specific ingredients); smaller, quick-cooking items such as green beans and shiitake mushrooms can be left whole. It isn’t necessary to dredge the ingredients in flour because my tempura batter clings well enough without it. But do make sure the vegetables and seafood are dry, and season the seafood with salt and pepper just before dipping it in the batter.
At the restaurant, I have a professional deep-fryer that regulates the oil temperature. But at home it’s easy enough to use large, deep cooking vessel and an accurate frying thermometer to monitor the oil. The pot should be made of heavy-gauge metal—cast iron or enameled iron are ideal because they retain heat so well. Use a pot at least eight inches deep so you can fill it with three to four inches of oil and still have a couple of inches on top to allow for splatters and bubbling. You’ll also need a mesh skimmer, called a spider, to lift the tempura out of the oil.
Use a mild vegetable oil with a high smoke point, such as canola or safflower oil. I like canola because it’s virtually tasteless. Be sure the pot is completely dry before adding the oil; water causes hot oil to splatter. If you plan to reuse the oil after frying tempura, let the oil cool completely and then strain it and store in a cool, dark place. Used oil turns rancid more quickly than fresh oil, so check it before using it again.
Heat the oil to between 350° and 360°F and monitor it periodically to maintain a constant temperature. If the temperature drops too much, the batter will absorb too much oil and you’ll get a ghastly result: greasy tempura. If the oil is too hot, the batter will brown before the food is cooked through.
A cornstarch and club soda batter buys time
Traditional tempura batter consists of just three ingredients: egg yolks, ice water, and flour. The yolks provide richness and flavor, and the flour gives structure. But the batter is tricky to use—it must be extremely undermixed to prevent gluten development, which would make the tempura tough, and it must be used within twenty minutes.
Since I’m busy enough in the restaurant without having to deal with fickle batters, I’ve come up with a version that’s less temperamental and just as superb as, if not better than, the traditional version. My batter, which uses cornstarch, club soda, and flour, contradicts the conventional wisdom of tempura, which is to always undermix the batter. In fact, this batter, which I call my “workhorse” batter, performs best when it’s smooth and lump-free; it’s virtually impossible to overmix it.
The cornstarch, which has no protein and therefore no ability to form gluten, keeps the tempura from getting tough. The carbonation in the club soda creates an airy batter, which produces light tempura. It’s true that some of the bubbles are lost during stirring, but if you set the batter over an ice bath to keep it cold, most of the aeration is preserved. Without egg yolks, the batter lacks a certain richness, so I compensate by whisking in minced fresh herbs or spices.
Although my flour, cornstarch, and club soda batter holds up well over time, it should still be prepared at the last minute since it performs best when freshly made. Sometimes the batter needs a bit of tweaking. Flours can vary in how much liquid they absorb, and humidity can play a role, too, so you may need to add a drop more club soda or a bit more flour to get the right consistency. The batter should be whisked until it’s very smooth and just thick enough to coat the back of a spoon like a custard sauce.
I think that tempura is most interesting visually and texturally when it has a translucent, almost lacy crust. If you decide that you prefer a thicker coating, you can add more flour to the batter.
Dunk in batter, lay in hot oil, and fry until crisp and golden
Once the vegetables are cut, the oil is up to temperature, and the batter is mixed, you’re ready to start frying. Prepare a workspace next to the stovetop, if possible (as described above). I keep a damp towel nearby in case I get overzealous with the dipping; this isn’t a tidy endeavor, in any case.
Immerse an ingredient in the batter, lift it out with your hand, and quickly lay it in the hot oil. You’ll be tempted to shake off excess batter, but don’t do it. The key is to lift out the fully coated item and immediately put it in the oil without a moment’s hesitation. This will probably feel unnatural at first, and it will definitely be messy, as batter drips between the bowl and the pot. But this unhesitating technique is essential to achieving the thin, crispy coating that makes tempura so enticing. If you feel uneasy using your hands, use tongs or chopsticks.
Fry the tempura in small batches. Frying just four to six pieces at a time helps keep the oil temperature from dropping suddenly and gives each piece enough space to cook. If the pieces float toward each other, act like a 1950s sock-hop chaperone and separate them with a firm nudge from your mesh skimmer.
Sprinkle salt, pepper, and any other spices on the tempura as soon as they come out of the oil so the seasonings stick. Since the delicate coating doesn’t last much longer than a few minutes, serve each batch of tempura right away. An open kitchen is an advantage; while your guests are enjoying the first round of tempura, you can be frying the next one. If that’s not feasible, you can hold the finished tempura in a 200°F oven while you complete the frying.
It’s traditional to serve the tempura with a dipping sauce of soy sauce and mirin, a sweet rice wine. The one I suggest here includes lemon juice and is intended to mimic the Japanese ponzu sauce.
How to cut vegetables and seafood for tempura
One of the delights of tempura is the interesting shapes that the food takes on during frying. You can take some liberties in how you prepare the vegetables, but be sure that they’re cut so that they’ll be tender inside just when the batter is crisp and golden. Here are some suggested cutting techniques. Remember to dry all ingredients thoroughly before dunking them in the tempura batter.
zucchini and yellow squash: cut on a sharp angle to make elongated ovals, 1/2 inch thick, or cut in lengthwise wedges, 3 to 4 inches long
bell peppers: core and seed, remove all pith, and cut lengthwise into strips, 1/2 inch wide
shiitake mushrooms: remove stems and fry the caps whole or cut out a decorative star on top
green beans: trim ends and fry whole
sweet onions: before peeling, cut into rings 1 inch (such as Vidalia thick; then pull off outer layer of skin or Walla Walla)
eggplant: cut in half lengthwise, cut half moons 1/4 inch thick; sprinkle lightly with salt and let sit for 20 minutes to purge bitter juices; rinse and pat dry
asparagus: trim off all of the woody base with a decorative bias cut
sweet potatoes and celery root: peel and cut into batons, 1/4 x 2 inches
carrots and parsnips: cut on a sharp angle to make elongated ovals, 1/4 inch thick
taro root: peel and cut very thin, 1/8 inch thick
lotus root: cut in cross sections to reveal the beautiful seed pod pattern, 1/4 inch thick
shrimp: peel and devein, leaving on the tail (and head, if you like); season with salt and pepper just before dipping into batter
squid: cut into rings; season with salt and pepper just before dipping into batter