Pickled walnuts are a traditional English pickle, made from walnuts.
Pickled walnuts have been a delicacy in England since at least the early 18th-century. They were mentioned in several literary works
The botanist Richard Bradley describes pickled walnuts in his 1728 book The Country Housewife and Lady's Director,
The beginning of this Month is the time to pickle Walnuts, for then the Walnuts have not began to shell, and moreover are not so bitter nor hollow as they will be afterwards; they will now be full flesh'd, and you will have no Loss. The following Method I learnt from Mr. Foord, a curious Gentleman of Buckingham, and has been experienced to be the best way. There is one thing indeed which must be regarded in this Pickle, which is, that every one does not love the Taste of Onion or Garlick; but that may be omitted as we please, only supplying the place with Ginger. [continues with actual recipe]
Charles Dickens in his book The Pickwick Papers, published in 1836. In chapter 49 he writes,
However, there he lay, and I have heard my uncle say, many a time, that the man said who picked him up that he was smiling as merrily as if he had tumbled out for a treat, and that after they had bled him, the first faint glimmerings of returning animation, were his jumping up in bed, bursting out into a loud laugh, kissing the young woman who held the basin, and demanding a mutton chop and a pickled walnut. He was very fond of pickled walnuts, gentlemen. He said he always found that, taken without vinegar, they relished the beer.
Pickled walnuts are also mentioned in Brideshead Revisited by Evelyn Waugh.
Pickled walnuts are still commonly eaten in England, particularly at Christmas served with an English blue cheese such as Stilton. They are also used in recipes, commonly cooked in beef dishes.
Pickled walnuts are made from the fruit of both common walnut tree varieties: Juglans regia, the Persian, royal, English or common walnut, and Juglans nigra, the black or American walnut.