Winehouse appeared with her 15-year-old protégé, who is her goddaughter, during her support slot for The Wanted at last night's iTunes Festival.
Despite a rapturous applause from the audience, the 'Back to Black' star didn't sing during a performance of Bromfield's debut single 'Mama Said', which she sang with the star on Strictly Come Dancing in 2009.
After Bromfield closed her set with 'Yeah Right', which is taken from her new album Good For The Soul, Winehouse returned to the stage to plug the soul singer's LP.
The duet marks Winehouse's first stage appearance since cancelling her European tour after a poorly-received gig in Serbia, in which she slurred her words and stumbled around the stage.
Watch the 'Yeah Right' music video below: