Given a choice between french fries and onion rings, most restaurant-goers opt for fries, which is tragic, but I get it. Fries are the surer bet because they’re simple to make: Just cut up some potatoes, fry them (twice, ideally) in bubbling oil until crisp and evenly golden, drain, and season. Very reliable.
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Ordering onion rings is a riskier proposition. Though sublime in their most perfect state—a crisp, light crust fully encasing a tender, savory circle of onion—there are so many ways for them to disappoint. The crust can break into shards and fall off the onion, robbing you of that interplay of crisp, toasty exterior and tender interior. Sometimes the onion pokes through the batter and, uninsulated, burns in the hot oil. And then there’s the classic problem of onion escape, where you take your first bite and the whole onion hoop slips from its shell, leaving you awkwardly slurping it up while holding the mostly intact carapace in your hand.
After too many sad restaurant experiences, I resolved to develop an onion ring recipe so that I could make them at home and enjoy guaranteed satisfaction every time. Choosing between craggy breaded rings and lighter battered rings wasn’t a problem; I opted for the latter because I consider it to be the pinnacle of onion perfection, each round perfectly enrobed in a pristine shell. I wanted mine to be delicately yet enduringly crisp without veering over the line to crunchy, and I wanted them to be evenly browned for both flavor and visual appeal.
Upgrade Your Onion
Onion rings’ crispy, fried coating is the star of the show—but that doesn’t mean the interior onion shouldn’t shine too. To punch up the flavor of the yellow onions inside our rings, we season the alliums with a mix of onion powder and confectioners’ sugar. The former doubles down on the allium flavor and contributes savory, roasty notes, and the latter gives the rings a subtle Vidalia-like sweetness.
Following a fairly straightforward recipe for my first attempt, I cut two large yellow onions into rounds, separated the rounds into rings, and soaked them in heavily seasoned buttermilk to impart flavor. While they soaked, I mixed up a simple batter of all-purpose flour, more buttermilk, and salt and pepper. I drained the onions and patted them dry (tempted to rush this, I soon discovered that batter doesn’t cling to wet rings). Then, I coated the onions in batter, fried them in hot oil, and transferred them to paper towels to drain. I salted them lightly, but the crystals mostly bounced or rolled off the smooth fried coating.
Though not the worst rings I’d ever had, they fell far short of my ideal. The crust was dense, crunchy, and underseasoned, first of all. And to my chagrin, I experienced onion escape upon my first bite, leaving me with a mouthful of coating-less onion and a handful of onion-less coating. To fix these problems, I’d have to address each element separately.
Science: Building a Better Batter
Flour Browns; Cornstarch Crisps
Some fried foods are coated in either flour or cornstarch, but this recipe calls for both. Flour contains proteins that readily take on Maillard browning, but its gluten is detrimental to texture (all-flour coatings fry up dense and tough). Cornstarch, on the other hand, contains no protein, so it doesn’t brown, and it also doesn’t form gluten, so it fries up airier and lighter than flour. Mixing the two starches captures the best of both worlds—attractive browning and a crisp texture.
Beer and Baking Powder Lighten
Baking powder and beer add carbon dioxide to the batter, causing it to expand during frying and become light and airy. (Beer also contains sugar, which contributes to browning and flavor.)
Enhancing the Onion
Sweet onions such as Vidalias and Walla Wallas aren’t always available, and red onions fry up unattractively mottled, so I decided to stick with two yellow onions, about 1 pound each, to serve six people generously. I reserved the ends and the innermost rings of the onions for another use because I found that they captured too much batter, which made for doughy rings.
Soaking the onions in a seasoned liquid only to pour it down the drain seemed wasteful, and patting them dry was tedious, so instead I tossed them with a dry seasoning mixture: confectioners’ sugar supplied a Vidalia-like sweetness, and salt enhanced the savory allium flavor. But why stop there when I always have a bottle of onion powder in the pantry? I tossed some of that in too. And when I saw that the salt (and, to a lesser extent, the sugar) started to pull moisture out of the rings, which made them harder to coat with batter, I stirred in some absorbent cornstarch.
To make the crunchy, dense crust a bit lighter and more crisp, I borrowed a trick I’d employed when developing a recipe for Korean fried chicken; namely, using a combination of all-purpose flour and cornstarch for my batter. It works because all‑purpose flour clings and browns nicely but fries up a bit crunchy, and cornstarch, which doesn’t brown or cling as well as the flour, is more lightly crisp. (A higher ratio of cornstarch to flour made rings that were too light, almost foamy, and pale.) Baking powder boosted the lightness a bit more. I tossed in the remainder of the seasoning mixture for an extra flavor boost that would also save me from trying to salt the rings post-fry.
Suspecting that a bubbly liquid would lighten the dense batter further, I used seltzer instead of buttermilk for the liquid, and it produced the lightest, crispest rings yet. But the seltzer didn’t add much flavor, so I tried the classic choice of beer. Like the seltzer, it made the fried coating light and crisp (and tastier than the seltzer rings), but the sugars in the beer also enhanced browning, so much that I found I had to lower the fry oil temp. Side benefit: Too-firm onions are the culprit behind onion escape, and frying lower and a bit slower meant that the onions had more time to soften before the coating overbrowned.
Solved: The Perennial Onion Ring Problem
Picture this: You’re at a restaurant, you eagerly take a bite out of an onion ring—and next thing you know, you’ve got a mouthful of denuded onion and a sad, empty, fried shell in your hand. This phenomenon occurs when the onions within the rings are undercooked and too firm—you can’t take a clean bite. Our solution? Cooking the rings lower and slower. Frying the onions at 360 to 375 degrees for about 4 minutes allows the internal onions more time to soften before their shells overbrown, so they yield along with the coating when bitten.
While onion rings this crisp and flavorful don’t really need an accompaniment to help them shine, I was in a celebratory mood. So I stirred together something akin to a burger sauce: mayo with a glug of ketchup, a bit of heat from pickled jalapeños and cayenne, and a bit of tang from added pickle brine.
To be safe, I’ll still order french fries when I’m eating out. But at home, I’ll be having perfect onion rings.