Nutmeg

Nutmeg was a brown seed used as a spice to flavour foods. (PROSE: The Roundheads, The Face-Eater)

It was also added to mashed potatoes. (PROSE: Damaged Goods)

Nutmeg was also use to garnish the top of sweet foods or beverages; served on top of rice pudding and on top of milk. (PROSE: Downtime, Sleepy) Organic nutmeg was used to top double-caffeinated cappuccinos; a favoured drink of the Fifth Doctor. (PROSE: Not So Much a Programme, More a Way of Life)

In wine
On Earth in the 17th century nutmeg was used to flavour wines. (PROSE: The Empire of Glass)

On Avalon in 2945 it was also used as a spice to flavour wine. (PROSE: The Sorcerer's Apprentice)