NEW YORK — It's a technique on the tip of a lot of parents' tongues — and maybe their children's too: Puree healthy fruits and vegetables, and sneak them into regular kid food like macaroni and cheese or chocolate pudding. Watch the kids unknowingly gobble down their vitamins, and smile.

But what's got people talking isn't just the good idea, but the fact that two cookbooks released a few months apart focus on the strategy in strikingly similar ways.

Throw in the fact that one is written by the wife of star Jerry Seinfeld, a waiting list for the book and you've got a recipe for intrigue.

First out of the gate in April was "The Sneaky Chef: Simple Strategies for Hiding Healthy Foods in Kids' Favorite Meals," by Missy Chase Lapine, published by the Running Press, an imprint owned by Perseus Books. (Disclosure: The AP has contracts with Perseus for its Stylebook and other publications.)

A former publisher of Eating Well magazine, Lapine writes about about how she developed a "hiding technique" to get her picky eating daughters to eat what she wanted them to.

Then came "Deceptively Delicious: Simple Secrets to Get Your Kids Eating Good Food," by Jessica Seinfeld, published in early October by Collins, a division of HarperCollins. In it Jessica Seinfeld tells of a weekly ritual she and her husband have of creating dozens of containers of vegetable purees to be added to meals for their three kids during the week.

Readers on amazon.com immediately began comparing the two, testing recipes to see which book they liked better. And after Seinfeld appeared on Oprah on Oct. 8, sales of the book took off.

No one is accusing anyone of plagiarism. The idea of putting pureed vegetables in kids food has been written about elsewhere many times, and recipes on the Internet abound for such dishes as brownies spiked with spinach and pudding with avocado. But the timing of the two books has certainly stirred more than appetites.

"The overlap in recipes seems pretty suspicious," wrote one reviewer on amazon. "It's a bit sad really."

Collins says it's just coincidence, but Perseus says some details closely mirror one another.

According to Steve Ross, president of Collins, his company received a 130-some page proposal from Lepine for her book in May 2006. The company rejected it because they believed it was similar to another book in the works called "Lunch Lessons" by Ann Cooper and Lisa Holmes.

In June 2006, Seinfeld submitted her proposal with the help of an agent, and HarperCollins representatives met with her, partly because of her high profile, Ross said.

At that meeting, staff who sampled her recipes for macaroni and cheese and meatballs were "wowed," he said.

"In person, she was such an articulate and passionate spokesperson and advocate for the idea of having your children eat nutritious foods," he said. The company acquired the rights to the book in June.

Meanwhile, Lapine got a deal with Running Press after an auction among six different publishers, she said.

Lapine's book came out in April, and a month later she saw a promotional brochure that included recipes and a book cover for Seinfeld's book, which she said was similar to her own book's logo — a woman holding carrots behind her back.

"I got really upset," said Lapine. "My visceral action was 'Oh my god.' I was, like, heartbroken. I knew there was a book coming out by a famous person that was so incredibly similar."

David Steinberger, president and CEO of The Perseus Books Group, said he wrote a letter to HarperCollins expressing concern about the similarities.

While Collins did modify the cover to put the carrots on a counter, Ross said that was not in response to the letter. The company made no other changes, Ross said.

"We reviewed the allegations and found them to be completely without merit," he said.

Steinberger said Perseus is trying to get more information on how the similarities may have happened.

Seinfeld said she has never seen or read "The Sneaky Chef."

"My book came from years of trying to get my own children to eat healthy foods — my own trial and error in my own kitchen," she said in a statement. "The idea of pureeing vegetables has been around for decades."

Seinfeld's agent, Jennifer Rudolph Walsh from William Morris Agency, said she and Seinfeld began discussing the idea in 2005. She said the book was already being bound when "The Sneaky Chef" came out.

Lapine said she is not accusing anyone of anything. But she said it does "hurt" to see someone else given credit for her method.

But with Americans focused on obesity and getting kids to eat better, both books are doing well: Seinfeld's will reach No. 1 on The New York Times bestseller list for hardcover advice books Oct. 28, and Lapine's will be at No. 9 on the paperback counterpart list, according to the newspaper.

Collins is working round-the-clock to keep up with demand, Ross said, with 2.3 million copies of the book expected to be in print by the end of January.

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