Chateau Cissac

Chateau Cissac was a wine made in France, from the appellation of Corbières. Nicolas had a bottle of Chateau Cissac as he awaited the countdown to CERN's destruction by dynamite, as he had read the Veritas. Nicolas had a few sips, from a glass, as he explained things to Bill Potts and Nardole, though he was already drunk. (TV: Extremis)

Behind the scenes
In the real world, Château Cissac wine is made in the region of France, specifically in the  appellation, rather than in Corbières. However, the bottle Nicolas is holding, once you get a sharp shot of it on the table, unmistakably says both "Chateau Cissac" and "Appellation Corbières Contrôlée".

Oddly, the circumflex accent above the 'a' (ie. â), in the company logo, is also not visible on the label.