Two moms. Trader Joe's. The Upper West Side. An (allegedly) "obnoxious" teenager. And one package of Trader Joe's brand Frozen Vegan Pad Thai With Tofu THAT WOULD TEAR THEM APART. This story seems like a pre-packaged viral ad campaign for the wildly popular supermarket chain, but it's actually a true and harrowing tale of Mom vs. Mom Gone Wild. The defendant is "amateur mezzo soprano" and grade school English teacher Marcella Caprario, who's accused of assaulting Dr. Cathleen London, a divorced mother of two and frequent TV talking head. The two ladies locked horns in the frozen food section of Trader Joe's on Broadway at 72nd Street last winter, and despite numerous plea deal offers, Caprario has demanded her day in court. Today, at last, is that day.

"Why should someone plead guilty to something they didn't do?" Caprario asks the Post. She fully admits that she slapped London, but maintains it was justified. The altercation began when her husband was blocked by one of London's sons as he tried to obtain his wife's beloved frozen pad thai. "You know how they have those awful pillars outside the frozen-food cases?" Caprario explains on behalf of millions of Upper West Siders who must somehow endure the vagaries of sub-par interior design. "Bill's there, trying to reach around them" to get to the pad Thai when London's teen son "seemingly intentionally kept trying" to thai-block Bill.

"So Bill says to Marcella, loud enough for the kid to hear, 'They don't even say excuse me,' " Caprario's attorney tells the tabloid. That's when London "hit the roof," and yelled at poor Bill, "He's just a child! Get that pole out of your ass!" Well, we never! Caprario claims she only slapped London after the doctor "charged at her" and invaded her personal space.

But she smacked her so hard she caused "redness, swelling and substantial pain"; Caprario's attorney calls that "reasonable force." And again, this is TRADER JOE'S pad thai we're talking about! His client faces a charge of misdemeanor assault, and she and her husband are expected to take the stand today in what some people (us) are already calling the Pad Thai Trial of the Century! All eyes are on Manhattan Criminal Court at this hour, and somewhere Anthony Weiner is breathing a sigh of relief.