Grapes are harvested from early February to late March. On arrival, they are pressed to juice, which is then briefly held before a light clarification step prior to inoculation with cultured yeast. The primary fermentation occurs in stainless steel tanks with a few, small selected parcels fermented in oak vessels for greater complexity. In May, the winemaking team assemble the Chandon Brut base from this selection of new base wines and reserve wines from previous years. The aim is to produce a blend with consistent style, complexity and character. All three classic Champenoise varieties are used and while the blend may vary from year to year, Chardonnay usually accounts for around 60% of the final composition. The reserve wines are stored in a combination of large oak barrels, barriques and stainless steel and comprise more than 20% of the final blend, adding maturity and further complexity to the Chandon Brut style. Following the secondary fermentation in the bottle the wine has extended ageing on the yeast lees, which contributes a range of complex, savoury characteristics to the finished wine. Perhaps more importantly, the yeast contributes to the texture and overall finesse of the bubbles in Chandon Brut, a result which cannot be achieved without this méthode traditionnelle. Individual bottles are then riddled and disgorged, and a small amount of dosage liqueur is added to finish the wine. After a further three months bottle age the wine is ready for consumption.