A kitchen was a room in which food was prepared.
The Seventh Doctor used lemonade to stick the Kandy Man's feet to the floor of his kitchen. (TV: The Happiness Patrol)
On Easter 1996, the Doctor's TARDIS crashed in the back of Amelia Pond's house. She invited the newly-regenerated Eleventh Doctor into the house, where he tried multiple items in the kitchen before finding just what he needed: fish fingers and custard. (TV: The Eleventh Hour)
The Eleventh Doctor claimed to have put a tap for lemonade in the kitchen of Uncle Digby's country estate. (TV: The Doctor, the Widow and the Wardrobe)
The TARDIS kitchen was the usual location of the food machine, (PROSE: The Room With No Doors) although it was known to "wander" the corridors. (PROSE: Christmas on a Rational Planet)