Mary Berry has said she will work with Mel Giedroyc and Sue Perkins again, but joked that a future project may involve gardening instead of baking.The Great British Bake Off judge also promised that tonight’s episode of the popular BBC One show is “the most difficult one we’ve ever had”.The finale of the seventh series will be the last time it airs on the BBC before it moves to Channel 4 next year.Berry, Giedroyc and Perkins will not move with the show, with co-judge Paul Hollywood the only member of the original team going to Channel 4. Berry told Chris Evans on BBC Radio 2 that her decision to stay with the corporation was made “straight away”.She said: “It was a gut feeling and I made it straight away for myself, having discussed it with my family and others. I’m very happy I’ve stayed with the BBC. Everything I’ve done has been with the BBC and I wanted to stay with them.”I’m sure the programme will go on to be a little bit different, but it will still be wonderful.”The remaining contestants – Andrew Smyth, Jane Beedle and Candice Brown – are hoping to rise to the occasion and be crowned the series winner.Rolls-Royce aerospace engineer Smyth, garden designer Beedle, and PE teacher Brown withstood the heat of the kitchen against nine other cake creators to reach the showdown for the title of 2016’s best baker. Berry said of the finale: “It really is the most difficult we’ve ever had, because you know, (it is) series seven and the showstopper is… we are wanting sheer perfection and they will be very nervous because they have watched every series.”The baking doyenne said of Perkins and Giedroyc: “We have made no decisions whatsoever, we haven’t actually all three got together, but we will do something because we’re good pals, and who knows what it would be?”Well, it may not be baking, you never know, it could be gardening. I’m a very keen gardener you know.”Tasks for the final BBC episode include a return to meringues for the signature bake, a technical challenge set by Berry that will ask the contestants to complete a British classic after being given just one instruction and no measurements, and a showstopper that is said to be the most complex set in the competition, with the most bakes requested for a challenge.As usual, the winner will be announced at a celebration attended by the family and friends of the three finalists, as well as the bakers they knocked out in previous rounds.The Great British Bake Off final airs tonight on BBC One at 8pm. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.