Rice Balls, Subtle and Showy Alike, at Omusubi Gonbei

I’d never seen a rice ball quite as large as the Bomb, whose heft in the palm calls to mind the smack of a line drive into the glove.

It comes entirely wrapped in nori and, when bitten into, reveals a mantle of impeccably fluffy rice, so white that the grains gleam. At its core lie flakes of grilled salmon, tuna tinged with Sriracha-spiked mayonnaise, and kombu for a pop of brine: three rice balls’ worth of fillings in one.

The Bomb is the creation of Omusubi Gonbei, a chain founded in Japan in 1999. Its first American outpost opened in 2013 in the food court of Mitsuwa Marketplace, a sprawling Japanese store in Edgewater, N.J. The second followed last spring, a counter tucked inside Katagiri grocery by Grand Central Terminal.

Its other rice balls, known as omusubi or onigiri in Japanese, are more traditional in ingredients and shape, neatly triangular, trussed with a band of nori or shielded by a shiso leaf like a strategically placed fan. But they, too, are larger than life: Omusubi Gonbei claims to use one and a half times as much rice as its competitors.

(This is true both here and at home in Japan. Omusubi Gonbei’s rice balls are giants in both countries, not supersized for American appetites.)

The plainest of onigiri is just rice with a press of salt from the fingertips and a stripe of sesame seeds on top. But there’s no just: The rice is grown in Japan without pesticides or chemical fertilizers, then shipped unprocessed and milled only once on the premises, to retain its flavor.

The white rice is exceptional, the grains swelling and clinging without clotting, so that the onigiri, gently patted into form by hand, stay fluffy and porous, not contracting with the loss of heat. The brown rice is arguably even better, slightly denser but wonderfully nutty and almost chewy.

Little signs are posted listing cooking and expiration times. The company advises that you eat the omusubi within four hours of its being made. I pushed that to the limit, and they were still delicious.

Onigiri start at $1 and top out at $3.80 for the Bomb, which could be a lunch unto itself. Ingredients might be mixed into the rice or buried at the center with a lone dab at the peak, like a flag.

The American menus — and the French: There’s an Omusubi Gonbei in Paris — are practically identical to those in Tokyo, save for the intrusion of that spicy tuna. It’s a generous concession to Western tastes, harking back to the spicy tuna rolls reportedly concocted by Japanese immigrant chefs in Los Angeles in the 1970s, to cater to the local fondness for condiments and the heat of Mexican food.

Some consider this sacrilege, the chile masking the flavor of the fish. Here, it’s a nice kick after all that soothing rice, like a muffled bolt of lightning.

Still, I preferred less showy ingredients: takana, pickled mustard greens with a faint, grounding bitterness; umeboshi, salty-sour pickled plum whose residual sweetness fights through; mentaiko (pollock roe), briny and close to cream.

Jako, dark-eyed glassine baby sardines, bodies ossified, taste like shattered deep-sea bacon. They’re threaded through a rice ball framed by shiso leaves, lending a green scent and hint of menthol.

A shrimp locked in tempura batter flares its tail, the nori draped around the rice like a tuxedo vest. The idea is smartly reprised with a fried oyster, another innovation for the American audience. Spam, a nod to the Hawaiian version of omusubi, is slapped over tamago, omelet laced with sugar and mirin: the classic death match — and love match — of salty and sweet.

Also on offer are miniature buckets ($3.50 each) of karaage, fried chicken in boneless pieces, all dark thigh, the meat rich from a bath in soy sauce. The crust softens a little as it sits, but still has fervor, its nubbly coat infiltrated by ginger, garlic and seasonings that the manager very kindly, very firmly refused to name.

Omusubi Gonbei is stationed right inside the entrance to Katagiri, which opened in 1907 as one of the first Japanese markets in the United States. (The original shop still stands on East 59th Street.) Venture deeper, and the missed opportunities multiply: bento boxes, sushi, steam rising from bowls of ramen.

No regrets. Just a promise to come back.

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