When my friend Steve*, wine lover and generous host, announced he was having a New Year’s Eve Party, I headed over with a bottle of 1980 Sauternes (a gift) to share with a few verified wine geeks, plus 30 or so non-wine geeky friends. Throughout the night, Steve opened 14 bottles of Champagne—some that guests brought, but many from his own small collection.

Steve, unfortunately, forgot to buy cheap bottles to slake people’s thirst for sparkling wine post-midnight, and at 1 a.m., some of his friends demanded more Champagne. Reticent to open another spendy bottle for his toasted guests, he did what any desperate host might do—he created his own. When no one but a few wine geeks were looking, he reached out the window to grab an inexpensive Tocai Friulano chilling on the fire escape and carefully poured it into an empty magnum Champagne bottle. For bubbles, he added San Pellegrino followed by seltzer water. Then, his unsuspecting wife walked around, pouring the nearly-clear-but-bubbly wine for her dancing friends.

Standing in the corner, the other wine geeks and I held our breath, waiting for an angry mob of duped revelers to form. Never happened. The thirsty group kept on dancing to Journey’s “Don’t Stop Believing” (they felt nostalgic for the Sopranos) and soon finished off the bottle.

Emboldened, Steve made up another bottle of Fauxpagne, this time with a Colombard/Ugni Blanc blend from Gascony in France, and feeling experimental, I donated a splash of the Sauternes to act as the sugar in the “dosage” (the extra wine, often sweetened, that’s added to Champagne before corking it to sell). After deeming it too sweet, Steve “acidified” with a squeeze of lime—a mistake we thought would cost us, since the new concoction tasted suspiciously like a bubbly margarita. We set the bottle in the ice bucket and waited. The partiers filled up and drank up and kept on dancing, no questions asked. To celebrate the creation of Fauxpagne, my nerd friends and I toasted with the last remaining bottle of the real stuff: the terrific Egly-Ouriet Extra Brut Grand Cru. Gosh, sometimes it’s great to be a geek.

*name changed to protect the guilty