Preheat oven to 350°F (175°C). Grease and flour a 10-cup bundt pan thoroughly.
In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt. Set aside.
In a large mixing bowl, cream together the butter, oil, and sugar until smooth and fluffy.
Beat in the eggs one at a time, mixing well after each addition.
Add sour cream, buttermilk, red food coloring, vanilla extract, and vinegar. Mix until combined.
Gradually add the dry ingredients to the wet ingredients and stir just until incorporated. Do not overmix.
Pour the batter evenly into the prepared bundt pan and smooth the top.
Bake for 45-50 minutes, or until a toothpick inserted into the center comes out clean.
Let the cake cool in the pan for 15 minutes, then invert onto a wire rack to cool completely.