Unlike his series' enigmatic, much debated ending, David Chase is pretty clear on how it all began.

The Sopranos' godfather took the stand Tuesday in a federal courtroom in Trenton, New Jersey, to whack allegations that he stole key ideas for his Emmy-winning HBO hit.

Chase, 62, is being sued for a cut of Sopranos profits by Robert Baer, a retired judge and former prosecutor.

Chase explained to jurors that, in the mid-‘90s, he went on a three-day tour with Baer of various Garden State locales, many of which wound up as haunts for Tony and the gang. But, Chase insisted, the sightseeing excursion had nothing to do with the plot themes of The Sopranos.

And when he heard of Baer’s lawsuit in 2002, Chase said he was floored.

“I learned I was being sued for half of everything I ever made," he told the seven-woman, one-man panel. "He claimed to be cocreator of the show. A man is not supposed to cry, but I felt like crying."

Paging Dr. Melfi.

Chase testified that the storylines for the mob drama sprang from his love of the classic TV series The Untouchbables and his experiences growing up in North Jersey, where he set his fictional family.

"The Sopranos is me," he said. "My mother, my uncles. [Baer] tried to take credit. It was my life, it was me. I try to be original in everything I do, and to have someone say I'm not original, well, it made me sick."

As far as any consulting services went, Chase said he directed his organized-crime questions not to Baer but to Manhattan D.A. Dan Castleman, who laid out the Mafia’s ties to garbage and construction unions, black-market schemes, shakedowns and the like.

"When I needed a murder, to have one guy kill another guy, he would plug in an element to make the story work," Chase said.

When queried why he never queried Baer about such matters, Chase said that the plaintiff "told me he was not a mob expert, and I witnessed that."

In his own testimony Monday, Baer laid said he briefed Chase in 1995 on places frequented by goodfella types, including a local pork store that eventually became The Sopranos’ Satriale’s.

"I don't know how I'll ever repay you," Baer claimed Chase said. To which the former judge replied: "Why don't you hold on paying me? If nothing comes of it, it's on the house. If something comes of it, you can pay me."

Baer claimed he also introduced Chase to detectives on the mob beat and frequently consulted on crime issues, all with the explicit assurance that if the series got picked up, he'd come aboard in an official capacity.

"I figured I'd rather take the risk," Baer said. "We talked about becoming a writer on the show if the show succeeded."

After that meeting, Baer's attorney, Harley Breite, said the two kept in touch and Chase even sent a draft of the pilot episode. But shortly after HBO greenlighted the show, Chase allegedly stopped taking Baer’s calls.

"He had blown me off," Baer testified. "[Chase and The Sopranos production] came to my town in Elizabeth and shot the pilot. He didn't even give me a courtesy call. He didn't even tell me he was in talks with HBO over the sale of the pilot."

Chase's camp cried foul at that assertion, saying Baer refused monetary offers from the Sopranos creator, something Baer has acknowledged.

U.S. District Judge Joel Pisano twice tossed the ex-judge's complaint, stating that the verbal agreement was too vague to be binding. However, an appeals court overturned the dismissals and reinstated the suit but allowed Pisano to curtail its scope to focus exclusively on money Baer claims he's owed for consulting services.

Baer is seeking $150,000 in damages.