By THÉRÈSE MARGOLIS

When most people think of Spanish wines, they imagine a crisp Crianza from Rioja, a silky Godello from Galicia, or maybe even a sparkling Cava from Penedès.

Indeed, Spain is the world’s third-largest wine producer, with thousands of varieties of robust red, fruity whites and floral rosés.

But then is there that other Spanish wine, that fortified, golden-hued sherry that your grandmother used to keep on the back shelf of her pantry and sip in the afternoon with her friends over a friendly game of canasta.

And while grandma may still have her secret staff of this liquid gold back in the cupboard, sherry, known in Spanish as jeréz, has come a long way since the time of stuffy English afternoon tea parties and dowdy ladies bridge tournaments.

Yes, jeréz is no longer the sole domain of coteries of sherry geeks or elderly spinsters.

In fact, this once-unappreciated wine is quickly becoming a favorite among cultured wine connoisseurs and millennial partiers alike.

Spurred on in part by the growing popularity of tapa restaurants and sherry bars, international sales of dry sherry have suddenly begun to increase.

A revival of premium, varieties such as fino and manzanilla has helped to arrest a long-term decline in sales of the fortified wine caused by the dwindling popularity of cream and sweet sherries.

Dry sherries are also being used in cocktails, from the classic rebujito to modern inventions involving padrón peppers or tonic water. One of the biggest crazes right now is mojitos made with sherry.

But most Jerez fans still prefer their sherry neat, and whether it be fino, amontillado or oloroso, worldwide consumer sales of that luscious “sack” so dearly loved by William Shakespeare’s Falstaff have increased by nearly 30 percent in the last five years.

That figure is a bit deceiving, however, because while sales revenues have gone up, the basic production –20 million bottles a year – has remained roughly the same. In other words, people are paying more because there is a growing demand for this tasty wine.

So what exactly is sherry and what’s all this talk about fortification?

Sherry is a wine made from white grapes (usually Palomino or Pedro Ximénez, but sometimes also Moscatel) in a tiny scrap of land known as the Jeréz Triangle in the province of Cádiz, in southern Spain near the Straits of Gibraltar. There are three main sherry producing regions in that triangle: Jerez de la Frontera, Puerto de Santa María and Sanlúcar de Barrameda.

Although sherry production starts off like that of any other wine, once its fermentation its complete, brandy is added to the mix to increase its alcoholic potency (hence, the fortification term).

There are four major sherry classifications: fino (a pale, delicate sherry), amotillado (an older, richer version of the fino variety), oloroso (a rich, dark mahogany hued wine) and the cream sherry (a blend of oloroso and the Pedro Jimenez grape with a sweet finish).

Sweet sherries – which account for only about 10 percent of total jeréz production today – are usually dark in color and are ideal as dessert wines.

But when choosing a dry sherry, opt for a light, straw-toned wine that will serve as an ideal accompaniment to cheeses, cured meats and tapas.

The traditions of sherry-making in Spain goes back over 2,000 years, when huge amphora were shipped to Rome and high alcohol content meant that the wine would travel well without spoiling.

As far back as the 12th century, huge quantities of the drink were exported to Great Britain, where the Spanish name jeréz and the Arabic word for the region, Sherish, were bastardized into the English name sherry.

Over the centuries, sherry’s popularity continued to bloom, and by the 19th century, producers could barely keep up with the demands of northern Europe, particularly England and Holland, which remain the two biggest consumers of the wine today.

Sherry is usually fortified using destillado brandy from the La Mancha region, and the distilled spirit is blended on a 50/50 basis.

This blend is then mixed with a younger sherry to stop the strong alcohol content from shocking the young jeréz and spoiling it.

Sherry is therefore a blend of many vintages, some a decade old.

Some dry sherries can be served chilled, but sweet sherries should be drunk at room temperature.