As trend-spotting goes for Chinese food on the East Coast, the basement food court at New World Mall in Flushing, N.Y., is the place to begin.

That's where Jack Chen, owner of Sakura Mandarin in Philadelphia's Chinatown, first spotted the spicy mix-and-match stir-fry bowls called ma la xiang gou. The direct translation, he says, is "numbing hot smells-good bowl."

But it might as well mean "Required Eating."

That's because in short order, those big salad bowls filled with heaps of customized ingredients tossed in complex, spicy sauce now anchor virtually every table at Sakura as the sharing dish of choice.

Every bowl comes with a hearty base of lotus roots, black mushrooms, noodles, kelp seaweed knots, and bean-curd skin.

What proteins you add on at $5.50 are your choice.

With a minimum of four add-ins, a $30 bowl is easily enough for three to share. Tripe is a must-have authentic taste for many Chinese customers. But we also loved the thin-sliced beef, big tender shrimp, and excellent fish fillets dusted crisp in spice.

One surprise is the now-popular Chinese ingredient of potatoes, which, sliced thin, really soak up the flavor of the sauce, a secret 10-ingredient brew that zings sweet-and-spicy with sugared soy and sesame oil, plus hot bean paste, chile oil, and enough heat and Sichuan peppercorns (if ordered "medium" or above) that you'll feel it ringing in your nose.

-Craig LaBan

Spicy stir-fry bowl, $30 (and up), Sakura Mandarin, 1038 Race St, 215-873-8338.