The 60-year-old grandmother-of-eight worked at the Central Surgery, Barton Upon Humber, North Lincolnshire, where she met her GP husband Tim.
Nancy was the outsider going into last night's show but triumphed thanks to a homemade gadget involving a drainpipe made by her GP husband for her final showstopper challenge.
Judge Paul Hollywood said: 'Nancy has been confident, creative and unafraid as a baker and that showed from the very start.'
Nancy told the BBC: 'Baking isn't difficult. You have to just keep trying and practising. I'm still learning techniques even now and I can sometimes make a complete mess of things! And when that happens, you just start again, keep your patience and try to gain your confidence.'
The show has 9m viewers, featured a dozen contestants and ran over the last 10 weeks.
* Do you have an unusual hobby that could feature in GP's Life section? Email email@example.com