Tea

Tea is both a plant grown on Earth and a drink made of the dried leaves of the plant submersed in hot water and allowed to brew. It originating in Asia. Before it spread to the west, the average English person, such as Will Chandler, who came from 1643, had it explained to him by the Doctor as "a noxious infusion of oriental leaves containing a high percentage of toxic acid". The Doctor then professed that he rather liked it. (DW: The Awakening)

The Doctor

 * During his time with UNIT the Doctor drank a lot of tea. Only the tea lady and the Brigadier could come into his lab. (DW: Terror of the Autons) He also made a habit of stirring his tea with anything available such as a silicon rod. (DW: The Three Doctors)
 * The Doctor had tea with four sugars during the dinosaur invasion of London. (DW: Invasion of the Dinosaurs)
 * Whilst in Victorian London the Doctor and Professor Litefoot attempted to educate Leela on the etiquette of tea. (DW: The Talons of Weng-Chiang)
 * While in the black hole domain of Brimo, the Doctor wrested part of the control away from Brimo by having one of her servants (which she had mentally created) serve him a cup of tea rather than kill him. (DWM: The Time Witch)
 * Nyssa once gave away some tea she'd found in the TARDIS, unaware that it had been a gift to the Doctor from the Emperor of China. (BFA: Spare Parts)
 * A potential future version of the Doctor met by his seventh incarnation had a particularly great interest in it. (DWM: Party Animals, Wormwood)
 * During the Shoreditch Incident the Doctor went to a cafe within central London and had a mug of tea, and discussed many things on his mind around the nature of evil and destiny. (DW: Remembrance of the Daleks)
 * Whilst at the Pinehill Crest Hotel leading up to the attempted invasion by the Scourge the Doctor wondered to Bernice Summerfield and Ace why tea made in a hotel room tasted worse than any other kind of tea. (BFA: The Shadow of the Scourge)
 * The Doctor whilst in his seventh incarnation was particularly fond of Lapsang Souchong tea, a style which Provost-Major Beltemst also appeared to enjoy. (NA: Original Sin)
 * When the Doctor's TARDIS was destroyed, the Doctor and Fitz sat around talking about all the tea they used to love drinking which is now gone. (EDA: The Shadows of Avalon)
 * Whilst in Cardiff the Doctor and Rose took tea with Charles Dickens at Gabriel Sneed's house, served by Gwyneth. (DW: The Unquiet Dead)
 * Tea was also able to assist the Doctor in recovering from his ninth regeneration. After saving the world from a Sycorax invasion in a dressing gown, he later described himself as like the fictional character Arthur Dent, who also had a great fondness of tea. (DW: The Christmas Invasion)

Companions

 * Brigadier Lethbridge-Stewart has occasionally used tea to break up the conversation, offering it to Zoe when she became worried of the Doctor's safety when he was pursuing Tobias Vaughn. (DW: The Invasion)
 * Sarah Jane Smith muttered that she could "murder a cup of tea". (DW: The Time Warrior)

Others

 * There is much tea (both with and without milk and sugar) in Professor Chronotis's rooms at St. Cedd's College, Cambridge. (DW:  Shada)
 * Captain Cook offered many people, and even when captured by the Psychic Circus was still able to drink, tea. (DW: The Greatest Show in the Galaxy)
 * Tibetans drank hot yak butter tea to fortify themselves against the cold of their native land. (DWM: Yonder... the Yeti!)
 * Alexander Christian searched the Doctor's House for tea bags (following his escape from a helicopter). (NA: The Dying Days)
 * Sarah Jane Smith and Gita Chandra share a thermos of tea. (SJA: The Day of the Clown)