Preheat your oven to 350°F (180°C). Line 16 cavities of two standard muffin pans with cupcake liners and set them aside for later.

In a large mixing bowl, sift together the cake flour and cocoa powder. Once combined, whisk in the baking soda and salt. Set aside.

Using a stand mixer with the paddle attachment, or a handheld mixer, cream together the softened butter and granulated sugar. Mix on medium speed for 4 to 5 minutes until the mixture becomes pale and fluffy.

Add in the egg and blend thoroughly. Follow with the oil, red food coloring, vanilla extract, and vinegar, ensuring the mixture is well-combined. Pause as needed to scrape down the sides of the bowl.

Alternately add the dry ingredients and buttermilk to the wet mixture, starting and ending with the dry ingredients. Incorporate the ingredients in three additions, mixing each one gently until just combined. Be cautious not to over-mix the batter.

Divide the batter evenly between the cupcake liners, filling each about halfway.

Bake for 15 to 18 minutes, or until the cupcakes spring back when touched lightly and a toothpick inserted into the center comes out clean. Remove from the oven and transfer the cupcakes to a wire rack to cool completely.

In the bowl of a stand mixer or using a handheld mixer, beat the softened cream cheese until smooth and creamy. Add the butter, mixing for about 30 seconds to 1 minute until the mixture becomes smooth and cohesive.

Gradually add the powdered sugar and vanilla extract. Continue mixing until all ingredients are fully combined, scraping down the sides of the bowl as necessary.

Once the cupcakes are completely cool, use a piping bag or a spatula to frost them with the cream cheese frosting.