Onion

An onion was a vegetable with a strong odour. When Starkey was forced to huddle with Thorne to be transported from Urlic back to Earth, Starkey asked Thorne if he had been eating "onions, or garlic." (TV: Lost Library of Ukko)

Spinthoz was the universe's biggest onion. The Eleventh Doctor visited it during peeling season, having thought it was a planet. (COMIC: Sticks & Stones)

Onions were added to vinegar in order to make pickled onions. (TV: World War Three)

Cheese and onion was a flavour of crisps. (PROSE: Citation Needed)