Iftekhar Murtaza, 29, of Van Nuys was found guilty on Nov. 22 of murder, attempted murder, conspiracy to commit murder, sentencing enhancements for multiple murders, and murder during the commission of kidnapping.
On Monday, a jury recommended the death penalty.
Prosecutors said Shayona Dhanak ended her two-year relationship with Murtaza citing her Hindu family's opposition to her dating a Muslim. Murtaza allegedly became angry about the break-up, believing that Dhanak's parents were responsible because they did not approve of the relationship.
Murtaza killed his ex-girlfriend's father, Jayprakash Dhanak, and sister, Karishma Dhanak, and nearly killed her mother, Leele Dhanak, before setting fire to their Anaheim Hills home in 2007.
Firefighters found the bodies of Jayprakash and Karishma Dhanak near a bike trail at Mason Regional Park in Irvine on May 22, 2007. Karishma appeared to have been burned alive and her throat was slashed.
Prosecutors said Murtaza orchestrated the attack in an attempt to win back his girlfriend.
Two other men, identified as Charles Anthony Murphy Jr., 28, and Vitaliy Krasnoperov, 28, were previously convicted for their connection in the murders.
In 2011, Murtaza married fellow Orange County Jail inmate Marissa Bilotti, who is also facing murder charges in an unrelated case.
Murtaza's sentencing date is scheduled for Jan. 10.