What is the traditional Champagne method of producing sparkling wine called?

The traditional Champagne method of producing sparkling wine is called méthode champenoise.

This method requires the second fermentation to take place inside the bottle that will eventually be sold. After the first fermentation creates a still base wine, the producer adds a mixture of wine, sugar and yeast, then seals the bottle. The yeast converts the sugar into alcohol and carbon dioxide, creating the bubbles.

The wine then ages on its lees, the spent yeast cells. Producers gradually move the sediment toward the neck, freeze or otherwise collect it, and remove it during disgorgement before adjusting the final sweetness and sealing the bottle.

The term méthode champenoise is closely tied to Champagne. Producers outside the region generally use terms such as traditional method because appellation rules protect the Champagne name and related terminology.