Preheat the oven to 350°F and liberally grease a 10- or 12-cup bundt pan with butter or cooking spray.
In a large microwave-safe bowl, combine the wine, butter, and cocoa powder. Microwave for 30 seconds, stir, and then microwave for another 20-30 seconds or until the butter is completely melted. Whisk the mixture until smooth.
In another bowl, whisk together the sugar, baking powder, baking soda, salt, and flour until well combined
In a third bowl, whisk together the sour cream, canola oil, vanilla, and eggs until smooth.
Add half the dry ingredients to the wine-cocoa mixture and stir until combined
Add the sour cream mixture to the wine-cooa mixture and stir until combined. Stir in the remaining dry ingredients and mix until the batter is smooth and just combined. Resist the urge to overmix the batter.
Pour the batter into the prepared bundt pan and bake for 50-60 minutes, or until a toothpick inserted in the center of the cake comes out clean.