Prosecutors say Janepsy Carballo lured her slain husband’s business partner to her home and fatally shot him in the back in cold blood.

But she claims self-defense — the man, Ilan Nissim, was a suspect in her spouse’s murder.

Hoping to convince a judge to grant her immunity under Florida’s controversial self-defense law, Carballo, 34, took the stand Monday, claiming she shot Nissim when he showed up unexpectedly at her house in May 2008 and attacked her.

“I just started shooting like there was no tomorrow,’’ said a crying Carballo, who faces a murder charge. “In my mind, he was reaching for a gun that I had seen with him. The shots were so loud, it freaked me out. In my head I was already feeling him shooting at me.”

But then prosecutors played a tape, recorded covertly in 2010 by a federal law enforcement informant as part of a narcotics investigation into Carballo. On tape, Carballo admits “I knew I had to do something” to Nissim because the cops weren’t going “to catch him.” Her toddler son was also wounded in the shooting.

Carballo wanted ‘an eye for an eye’ and for [Nissim’s] daughter ‘to grow up without a father, just like my son,’ she said on the tape.

But Carballo claimed she was just talking tough.

“That was me, two years after the fact, embellishing the story to [the informant]. I didn’t want him to think he could take advantage of me,” she said. “I knew he associated himself with some dangerous people.”

Miami-Dade Circuit Judge Beth Bloom will hear more testimony Tuesday in the motion for immunity before making a decision.

The controversial 2005 Stand Your Ground law eliminated a citizen’s duty to retreat when using lethal force to meet a threat of harm. The law also allowed judges greater leeway to dismiss a charge based on a self-defense claim.

The law came under scrutiny earlier this year when police initially declined to charge a self-proclaimed neighborhood watchman in the killing of an unarmed teen in Sanford. The gunman is now awaiting trial for murder.

Carballo’s husband, Orlando Mesa, 37, was gunned down April 20, 2008, by black-clad men in a white Toyota just outside their North Miami house. The couple’s toddler, Noah, 20 months old, survived with wounds to his arm and leg.

Shortly before his death, cops seized two large plastic bags of marijuana from his trunk, plus $16,000 in cash. Most of it was returned to Carballo after she showed the city she won it in the lottery.

On the stand Monday, Carballo admitted her husband was an “entrepreneur” who worked a mechanic and dealt drugs.

After the killing, his wife made a hysterical plea for help at a news conference at the North Miami police station.

On Monday, she again burst into tears and cried often, claiming her husband may have been targeted by Nissim because Mesa had given him $180,000 for a real estate deal, money she said was later stolen.

Carballo claimed she was terrified of Nissim, who tried to call her after her husband’s murder. But Carballo testified she went to the home of Nissim’s family at one point to talk to him.

On the day he was shot, Carballo claimed Nissim showed up at her home as she was packing to move. He began snooping around the house, helped her remove some speakers, then grabbed her demanding to know the location of a warehouse where her slain husband kept his property.

Prosecutors said Carballo shot Nissim six times in the back.

An autopsy determined that Nissim “was either lying on the ground or was bent very far over when he was shot,” according to the arrest warrant.