Champagne as we know it is made in two stages: a first fermentation to convert grape sugars to alcohol (like in almost all wines), and a second fermentation in bottle to create and capture the bubbles. The ‘wine’ at the end of the first fermentation is called vin clair, and the best ones are often delicious in a high acid, electric fashion. High quality vin clair is a prerequisite for making great Champagne, and in turn great vin clair is only possible where the terroir is superb, the farming immaculate, and cellar practices prudent.
The primary grapes of Champagne are Pinot Meunier, Pinot Noir (both at just over a third of all plantings), and Chardonnay (about a quarter). Each of them prefers different soil types and expositions, but the best sites are typically in the middle of the slightly concave slopes, where there is enough clay topsoil to sustain the vines as they root themselves in the chalk bedrock. Good farming is critical to retaining this topsoil without the aid of large amounts of artificial compost; the planting of cover crops (to reduce erosion and provide natural composting material) and gentle ploughing (to aerate the soil) are two of the most common techniques.
A Pinot Meunier vin clair is often intensely fruity, while its cousin Pinot Noir is usually more complex, less forward. Chardonnay, on the other hand, is minerally, dense, and typically the most acidic. When blended in the right proportions, the resultant vin clair is much more than the sum of its parts, and requires less trickery in both the tirage (added to start the second fermentation) and dosage (to top up the bottles) to be a delightful tipple.