Preheat the oven to 350°F (180°C), or 160°C if using a fan oven.
Make the Cake: In a medium bowl, whisk together the all-purpose flour, unsweetened cocoa powder, baking soda, and salt. Set aside.
In a large bowl, beat the granulated sugar, oil, and softened butter with an electric mixer until pale and fluffy.
Add the eggs, red food coloring, pure vanilla extract, and distilled vinegar to the butter mixture. Mix until well combined.
Add half of the flour mixture to the wet ingredients and mix on low speed until just combined.
Pour in half of the buttermilk and mix again. Repeat with the remaining flour mixture and buttermilk, mixing after each addition.
Gently fold in the mini chocolate chips, ensuring even distribution.
Spray a 12 or 10-cup bundt pan with baking spray, ensuring all areas are well-coated. Use a pastry brush if needed to reach crevices.
Pour the batter into the prepared bundt pan and spread it evenly.
Bake in the preheated oven for 45–50 minutes, or until a toothpick inserted into the center comes out clean.
Let the cake cool in the pan for 10 minutes, then carefully invert it onto a wire rack. Remove the pan and allow the cake to cool completely.
Make the Cream Cheese Frosting: In a stand mixer or with a hand mixer, beat the softened cream cheese and butter together until smooth and creamy.
Add the pure vanilla extract and mix until combined.
Gradually add the powdered sugar, 1 cup at a time, mixing well after each addition.
If the frosting is too thick, add heavy cream or milk, 1 tablespoon at a time, until it reaches a smooth, spreadable consistency.
Frost the Cake: Transfer the frosting to a piping bag fitted with a round tip.
Pipe the frosting onto the cooled cake by starting at the outer edge of the cake and piping a thick line toward the center hole. Repeat this process all around the cake, slightly overlapping some lines as needed to create the classic look.