Prepare the Bundt Pan
Preheat your oven to 350°F (175°C). Grease and flour your Bundt pan to prevent sticking.

Mix the Wet Ingredients
In a large mixing bowl, combine the vegetable oil, buttermilk, and granulated sugar. Mix until well combined. Add the eggs one at a time, beating well after each addition, then stir in the vanilla extract.

Combine Dry Ingredients
In a medium bowl, whisk together the all-purpose flour, cocoa powder, baking soda, salt, and red food coloring. Gradually add the dry mixture to the wet ingredients, mixing just until combined. Do not overmix; a few lumps are okay.

Create the Marble Effect
Divide the batter in half. Leave one half as the red velvet batter. For the chocolate portion, fold in a little extra cocoa powder for a darker chocolate swirl. Spoon alternating layers of red and chocolate batters into the prepared Bundt pan. Use a knife or skewer to gently swirl the batters together to create a marbled effect, without overmixing.

Bake the Cake
Place the Bundt pan in the preheated oven and bake for 50–60 minutes, or until a toothpick inserted in the center comes out clean. Remove from oven and let the cake cool in the pan for 15–20 minutes.

Cool and Frost the Cake
Carefully invert the cake onto a wire rack to cool completely. Once fully cooled, drizzle cream cheese frosting over the top, letting it cascade down the sides for a beautiful presentation.