Which Tolkien short story features a farmer who faces the giant Gogmagog?

Farmer Giles of Ham features a farmer who faces the giant Gogmagog.

Tolkien’s Farmer Giles of Ham was published in 1949. It is a comic medieval fantasy about Ægidius Ahenobarbus Julius Agricola de Ham, commonly called Farmer Giles. After a chance encounter with a dragon, Giles gains a reputation as a hero and becomes involved in larger dangers.

The story includes the giant Gogmagog, as well as the dragon Chrysophylax Dives. Its mock-heroic tone and play with names, titles, and local legend distinguish it from the grand epic style of The Lord of the Rings.

Smith of Wootton Major was published in 1967 and concerns a magical star and a cook’s apprentice. Leaf by Niggle is an allegorical story about an artist. The Father Christmas Letters are a collection of Tolkien’s illustrated letters to his children, not a tale about Farmer Giles.