To say a dish is spicy is to say a woman is beautiful. Helpful? Yes. Telling? No. Consider the difference between mustard, peppermint, and the main topics of this blog post, red chilis and Szechuan peppercorns. Mustard, horseradish and wasabi are thiocynates, pungent firecrackers that live in the cavities of your nose. They are Reese Witherspoon and Zooey Deschanel. Peppermint is mentholated and cool, Katharine Hepburn on a crisp morning.

Last night, I got to experience the family of alkylamides, the class of pungent chemicals that most strongly affect the mouth. Legend Restaurant in Chelsea is considered by many to be the best Szechuan restaurant in NYC. Fresh off a great write-up in the New York Times, the restaurant was packed with locals, foodies, and concerned and perhaps slightly violated Chinese regulars.

In the must-order Chongqing Diced Chicken with Red Chili and Szechuan Peppercorn (above), we got hot chilis that happened to be red, but didn't have that red-hot taste you associate with Tabasco. They were dried and burned and tasted a bit like the forest and fallen leaves. The Szechuan peppercorns were hot in a buzzy battery sort of way, and opened up your palate like a flute of champagne. Contrary to what the picture might suggest, this isn’t a brutal dish unless you bite a chili with a lot of seeds. She is J.Lo -- assertive yet relatively mild until you mess with her.

In the Ma Po Fish and Tofu, the hotness lived in a rounder way. The spiciness is infused in fat, which makes the sauce beat more steadily and with greater coverage. This was my favorite dish. She has a mysterious edge, a subtle way to get under your skin. As Harold McGee says, there are types of pungency that make you "conscious of simply breathing."