Preheat your oven to350°F (175°C). Grease a 9-inch round baking pan and line it with parchment paper for easy removal of the cake later.
In a mixing bowl, sift together the all-purpose flour, cocoa powder, baking powder, baking soda, and salt. Set aside.
In another mixing bowl, cream together the softened butter and granulated sugar using an electric mixer or whisk until light and fluffy.
Beat in the egg until well combined, then add the buttermilk (or milk and vinegar mixture), vanilla extract, and red food coloring. Mix until the batter is smooth and the color is evenly distributed.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix, as this can result in a tough cake.
If desired, fold in the semi-sweet chocolate chips for an extra decadent touch.
Pour the batter into the prepared baking pan and spread it out evenly with a spatula.
Bake in the preheated oven for 20-25 minutes, or until a toothpick inserted into the center comes out clean.
Once baked, remove the cake from the oven and allow it to cool in the pan for about 10 minutes. Then, transfer it to a wire rack to cool completely.
Once the cake has cooled, spread a generous layer of cream cheese frosting over the top and sides.
Slice and serve your delicious Red Velvet Cookie Cake, and enjoy every bite of this irresistible dessert!