Salt roasting is not new. Along the Mediterranean, it has been used for centuries to keep fish flaky and moist. In China, the Hakka people for more than 2,000 years have roasted chickens by burying them in hot salt. “No one is reinventing the wheel here,” says Fabio Trabocchi, chef-owner of Fiola and Casa Luca. “This is one of those ancient culinary techniques that still resonates with us today.”
The technique, which involves burying the vegetables in dry salt or beneath a crust of salt and egg whites, has obvious appeal to chefs. It roasts! It steams! It seasons! And wait, there’s more. It also helps to gussy up the description of otherwise humble root vegetables on the menu. When a salt crust is presented and cracked open tableside, as chef Alain Passard does at L’Arpège in Paris, the technique might even justify a price hike.
“It’s the closest thing to sous vide you can get for the home cook,” says Dan Barber, chef at New York’s Blue Hill, referring to that other fashionable cooking technique, in which meats and vegetables are sealed in plastic and cooked in a water bath at very low temperatures to seal in flavor and promote even cooking.
“The name of the game is consistency,” says Adam Sobel, the chef at Washington’s Bourbon Steak before moving this year to RN74 in San Francisco. “So if this gets you a perfectly evenly cooked beet, why wouldn’t you do it?”
I found out the hard way.
My first attempt was dry-roasting beets. I bought two bunches, making sure that the beets were of similar size. I scrubbed them clean but left on the skins to prevent the salt from penetrating too deeply. Next, I poured kosher salt about an inch thick in the bottom of a small pan and layered the beets on top. I covered the beets with more salt and stuck them in the oven, preheated to 325 degrees. So far, so good.
Recipes advised that the beets would take about 45 minutes. But the timer buzzed, and the beet I pierced with a knife to test for doneness was still as hard as a rock. I checked again at an hour and then another half-hour later. I was afraid to check too often, lest too many punctures of the skin render the beets inedibly salty.
At one hour and 45 minutes, my tester showed they were done, and I pulled the beets from the oven. While they were still warm, I peeled them. I glazed them with butter, then topped them with chopped chives, chervil and grated ricotta salata.
They were . . . good. Nicely seasoned. But it was Sobel’s inspired pairing of herbs and cheese that made them special. Disappointingly, a few of the beets still had a slight crunch. (So much for that promise of even cooking.) It would have been a whole lot easier to bake them in a foil packet.
I had higher hopes for the more traditional salt crust, a kind of igloo made with egg whites. Various chefs had suggested first whipping the whites to soft peaks or to stiff peaks, or just stirring them with the salt until the mixture resembled wet sand. I went for the simplest technique, blending about one pound of salt into eight egg whites, enough to roast three baseball-size celery roots. I packed the salt mixture around the vegetables until they looked like three lumpy snowballs in a roasting pan, then baked them for two hours at 350 degrees.
There was no checking for doneness, because my sharp paring knife could barely penetrate the crust — at least without cracking the whole thing wide open, which would have been the point of no return. Thankfully, when I finally did crack it open, there was no resistance to the knife. The celery root was cooked evenly, and it had an intense sweetness I hadn’t expected after my first flop. Rather than mix the root in with mashed potatoes, as I had planned, I sliced it thinly and served it in an impromptu salad with grapefruit, celery leaves and crushed hazelnuts and drizzled with olive oil.
Was it worth all the trouble? Food scientist Harold McGee says no. “Salt-baking root vegetables doesn’t have much to offer beyond simple baking,” he says. “The salt crust will moderate and even out the oven heat, and it may slightly reduce moisture loss. But the effects on flavor and texture will be minimal. Vegetables just aren’t as sensitive to cooking conditions as meats and fish.”
Grace Young, the author of three Chinese cookbooks, also doesn’t bother with salt-baking at home, even for that classic Hakka chicken. “Salt-baked chicken is absolutely delicious. However, done in the home kitchen it is one pain in the neck,” she says. “You need six pounds of salt. It’s difficult to check for doneness. I’ve always wanted to run a recipe for it in one of my books, but I’m afraid I’ll piss off my reader.”
For me? It depends. During the 15 minutes it took me to scrub my roasting pan free of salt crust, I would certainly have said no. I might try it again if the vegetable were the star of the plate rather than a side dish or one component of a salad. On the whole, though, the latest fashion for cooking root vegetables seems best left to chefs, just as peep-toe boots and fedoras are best left to “it” girls.
My advice: Go out to eat salt-roasted vegetables while they are a menu must-have.
Black is a former Food section staffer based in Brooklyn. On Twitter: @jane_black.