ONE finger. The left index, to be exact.

That’s all I was allowed to touch my partner with during last weekend’s orgasmic meditation session at the OneTaste center in Little Italy.

“Usually, we would have you wear rubber gloves,” says instructor Robert Kandell, “but since you two are dating, it’s not necessary.”

With that, he guides my digit directly onto the sweet spot of a beautiful young woman who asked to be called Layla in this story.

While most meditation involves sitting still and breathing deeply, orgasmic meditation (“OMing” for short) requires a partner and is a heck of a lot more intimate. Layla had agreed to try it out, and lay on her back on a mat in front of me, unclothed from the waist down.

I sit to her right, being taught a subtle finger movement that would make Buddha himself blush.

“Relax,” says co-instructor Racheli Cherwitz, who along with Kandell lives at the OneTaste Center in San Francisco. I couldn’t tell if Layla or I were more nervous. We’re not used to having an audience.

“Society calls orgasm the moment of climax,” Cherwitz goes on. “But that’s not necessarily the goal here.”

If it all sounds kind of crunchy, that’s because it is. OneTaste is an organization founded in 2004, with the goal of fusing spirituality and sexuality, and orgasmic meditation — something of a signature practice — is seen as a way of directly accessing spiritual energy and of breaking through the barriers around sexual contact. The technique is practiced either in a group setting or privately between couples, and is being taught here next month in a series of workshops at the downtown center. Layla and I lucked into a private tutorial.

Most OMing begins with an “inventory,” in which I’m supposed to tell Layla exactly what her honey pot looks like. While she’s a stunningly good sport about accompanying me to the OMing itself, she refuses to submit to this initial step.

“I am not used to one person being that aware of my hoo-ha,” she tells me later, “let alone three people staring down at it and talking about where to put your hand and how fast to rub.”

So, skipping the inventory, we proceed directly to “the stroke.”

Basic OMing is all about touching the woman, nothing else. It was a bit strange to be pulled back to third base after hitting home runs, but the position is familiar to dozens of OneTaste members here and in SF who practice OMing every morning at 7. (There are advanced courses where focus shifts to the guy, but again, climax is not the goal.)

“Remember, it’s just the two of you having an experience together,” says Kandell.

Indeed, after just a few minutes of OMing, I feel a most unusual sensation. Not the kind of excitement you’d feel if Adriana Lima and Bar Refaeli invited you to share a hot tub, but more like throwing back five shots of bourbon and then going for a fast run around the block. It’s a heady buzz, mixed with equal parts wooziness and intensity of focus.

Layla tells me later that she felt the same thing, and was left “shaking like I just touched a live wire.”

It’s not an unusual response, according to OneTaste co-founder Nicole Daedone. She is also visiting from SF this week to teach classes on intimacy, including one tonight in Midtown. The next OMing course in New York begins April 25 and is included in a OneTaste membership that costs $300.

“You are dealing with the most potent energy there is,” Daedone explains, while Layla and I sit buzzing. “OMing is the most the direct, clean access we have to that energy.”

Daedone should know. There was a time when she was OMing five times a day, and says that in the past 14 years she has instructed thousands

of students, ranging in age from 18 to 78.

“I understand it seems weird before you try it,” she says.

“But once you do, it’s like, oh, this makes sense. Thirty years ago, yoga was also seen as weird. I think 30 years from now, OMing will be as common and accepted as yoga.”

Hear that, personal trainers? Start flexing those index fingers!

jsilverman@nypost.com