Mary Berry (in-universe)

Mary Berry was a celebrity chef.

Biography
The Third Doctor spent a summer with her on a narrowboat in the Cotswolds. (PROSE: Twice Upon a Time)

Mary Berry assisted Eddie Redmayne when he contacted the Twelfth Doctor in the TARDIS. She acted as his personal cook. (TV: Looking for Pudsey)

Appearance
The Twelfth Doctor thought Mary Berry resembled his first incarnation; (PROSE: Twice Upon a Time) the Twelfth Doctor even referred to his earlier incarnation as Mary Berry, (TV: Twice Upon a Time) but the reference was lost on the First Doctor as he had yet to meet her. (PROSE: Twice Upon a Time)

Behind the scenes
Mary Berry portrayed herself in Looking for Pudsey.