Which coffee preparation technique involves using a filter?

Drip brewing is a coffee preparation technique that involves the use of a filter, making it distinct from the other methods listed. In this technique, ground coffee is placed in a paper or metal filter. Water is then heated and dripped over the grounds, allowing the liquid to extract flavors from the coffee as it passes through the filter, which holds back the coffee grounds.

The filtering process is essential in drip brewing because it ensures that only the brewed coffee, free of grounds, is collected in the carafe or pot below. This method is widely used due to its convenience and ability to brew larger quantities of coffee at once.

The other techniques listed do not primarily rely on a filter in the same way. Espresso is made by forcing hot water through finely-ground coffee without a traditional filter. Cold brew involves steeping coffee grounds in cold water for an extended period and is typically filtered afterward but does not utilize a filter during the steeping process itself. The French press uses a metal or plastic mesh plunger to separate the grounds from the brewed coffee, resulting in a more robust drink since some fine particles remain in the beverage. These variances in preparation techniques highlight why drip brewing stands out for its reliance on a filtering system.