Preheat your oven to 350°F (175°C) and line a 12-cup muffin tin with paper liners. Set aside.
In a large mixing bowl, whisk together the flour, cocoa powder, sugar, baking soda, and salt until no lumps remain and the cocoa is evenly distributed.
In a separate medium bowl, whisk the egg, buttermilk, vegetable oil, vinegar, vanilla extract, and pink gel food coloring until smooth and fully combined.
Pour the wet ingredients into the dry ingredients and gently fold with a spatula just until no streaks of flour remain. Do not overmix — a few small lumps are fine.
Divide the batter evenly among the cupcake liners, filling each about 2/3 full. A large cookie scoop works perfectly for this.
Bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs. Do not overbake.
Remove the cupcakes from the tin immediately and transfer to a wire rack to cool completely before frosting, about 45 minutes.
While the cupcakes cool, make the frosting: Beat the softened cream cheese and butter together with a hand mixer on medium speed until smooth and fluffy, about 2 minutes.
Add the sifted powdered sugar one cup at a time, beating on low speed after each addition. Once all the sugar is incorporated, add the vanilla extract and beat on medium-high for 2 minutes until light and airy.
Transfer the frosting to a piping bag fitted with a large star tip and pipe generous swirls onto each cooled cupcake. Serve immediately or refrigerate until ready to serve.
