The poised star held her head high as she walked into the Isleworth Crown Court wearing a sleek black coat over a suit. Her hair had been styled into soft waves.
Her impeccable appearance sent out a strong message from the TV personality, who has maintained a dignified silence in the wake of the claims against her.
Nigella went on to say in court that the drug allegations are "false".
Meanwhile, some of her famous friends jumped to her defence on Twitter. "#teamnigella," said Dawn O'Porter, while Jemima Khan wrote, "If there was ever a harmful charlie addiction, it was only to Saatchi himself."
Stephen Fry also spoke out about the issue, saying, "I know and adore Nigella and just can't bear the vilification she's getting #TeamNigella" and Lauren Laverne wrote, "Blue sky thought: applications for UK citizenship judged on the candidate's #TeamNigella status #Thinkaboutityeah #Noideaiswrong."
The celebrity chef appeared at Isleworth Crown Court on Wednesday morning to give evidence against her former personal assistants Elisabetta and Francesca Grillo, who stand accused of fraud.
The Italian sisters allegedly spent nearly £700,000 on luxury goods using credit cards.
They deny the charge, which is said to have taken place between January 2008 and last December, and have claimed that they were allowed to use the cards in exchange for covering up Nigella's drug use.
Nigella categorically denied their allegations. She said her court appearance came after a "long summer of bullying and abuse", and that following the now infamous "awful incident at Scotts (restaurant)", false allegations of drug use began circulating on a "PR blog".
She claimed that these allegations were "dedicated to salvaging" the reputation of her ex-husband Charles Saatchi, "and destroying mine".
Of the millionaire art collector, she added, "If I did not go back to him and clear his name, he said he would destroy me."