Roots, who has seven children, is said to have lied when he told the dragons that his gran had passed on the recipe to him.
Tony Bailey, 52, made the accusations in the High Court in London yesterday.
Bailey, who ran a food stall with Roots for 17 years, said:  “I showed him how to make it. Levi took the recipe. I gave it to him.”
Bailey, a Jamaican-born chef is seeking a £300,000-plus share of the food mogul’s profits, made after supermarkets across Britain started selling Reggae Reggae sauce.
Bailey added, “Levi knows the truth.”
Roots, 53, of Brixton, South London, whose real name real name is Keith Valentine Graham, won £50,000 of investment for his jerk chicken relish from Dragons Peter Jones and Richard Farleigh on the 2007 BBC show.
He is now a millionaire with a growing range of sauces and a food line.
His lawyer put it to Bailey: “Every proud Jamaican believes he has his own special method to make jerk chicken.
“But the general basic ingredients are the same aren’t they?” Bailey replied: “Many people make it differently.”
The hearing continues.