The author of acclaimed restaurant memoir Stuffed returns with two fictional sleuths in To My Dearest Friends (Reviews, Jan. 1).

Your protagonists are two women, 62 and 59, on the trail of their late mutual friend's secret lover. Is this the first time you've written at length about characters at midlife?

It is. I had something I really, really wanted to say—I wanted to talk about the burden and responsibility of unwanted information. I've been getting it since I was three, and I've never known what to do with it. It's very hard to do nothing. And these two are my generation. We're the generation that thought that we could change things, and now that we're getting older, we're not going to accept the inherited ideas of aging. We're intolerant of being miserable. Nan and Alice have that quality.

You manage to convey complex feelings without being preachy.

I don't like being lectured to when I read. If someone sounds pedantic, I put the book down. Originally, this novel was twice as long. I just cut out anything that smacked of that.

For the characters, it seems linked to their identities as New Yorkers, especially the humor.

Well, everyone in New York is pretty funny.

Restaurants are big, too. What would Nan and Alice's favorites be?

In the book they meet for lunch each time at Bergdorf's, and they have a Gotham Salad, their late friend's favorite. It really is a great salad. I should tell you that—my father invented it. He was the first person to chop a salad. I don't know if that's helpful. [Laughter.] I think they use the same Thousand Island Dressing. But let's see. Nan and Alice have budget restrictions, so for everyday, Nanny loves Rack & Soul on Broadway and 109th. Or Pascalou. Both are in the nabe, on the Upper West Side. Alice prefers Gabriel's; they know her there.

Do you find that growing up in a big restaurant family makes is easier to do characterization?

I did feel that every form of human behavior was displayed in my family, from taking the high road to being a con man. It was a full-blown family, and there were 17 of us. If you kept your eyes open, you saw a lot. And I love to watch people.

So it helps in moving from memoir back to fiction?

In memoir, people give you their characters. In a novel you have to create them, even if you draw on people that you know. You want to make a whole new person.