NEW YORK, NY March 14, 2008 —Why does mango irritate some peoples' skin?

How many different ways can you sear a steak?

Why is acid necessary to poach an egg?

And what exactly does it mean to sous-vide?

To answer those questions and thousands more, curious cooks have been consulting the quintessential reference book "On Food and Cooking" for more than 20 years.

Food scientist Harold McGee is the book's author. He's also a frequent contributor to The New York Times.

To the delight of New York City "foodies," he's giving a seminar in the city this weekend and he joins us now.

The Harold McGee Lecture Series is March 15 - 17 at the French Culinary Institute in SoHo. Go to www.frenchculinary.com for more information.