Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

Whisk together the flour, cocoa powder, baking soda, and salt in a bowl.

Beat the softened butter, granulated sugar, and brown sugar until light and fluffy, about 2–3 minutes.

Add the egg, red food coloring, and vanilla extract, then beat until well combined.

Combine the dry ingredients into the wet mixture gradually, mixing until just combined.

Fold in the white chocolate chips if desired.

Scoop rounded balls of dough onto the prepared baking sheet, spacing them about 2 inches apart.

Bake for 10–12 minutes, until the edges are set but the centers are still soft.

Cool the cookies on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely.

Make the frosting by beating together cream cheese, butter, powdered sugar, vanilla extract, and milk until smooth and creamy.

Frost the cooled cookies as desired.