Prepare the dry ingredients: In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt. Set aside.

Cream the butter and sugars: In a large mixing bowl, use a hand mixer or stand mixer to beat the softened butter, granulated sugar, and brown sugar until light and fluffy, about 2–3 minutes.

Add wet ingredients: Beat in the egg, vanilla extract, and red food coloring. Mix until smooth and evenly colored.

Combine the batter: Add the dry ingredients to the wet mixture in two parts, alternating with the buttermilk. Mix gently after each addition until just combined—don’t overmix, or the cookies may become dense. Fold in the chocolate chips.

Chill the dough: Cover the bowl with plastic wrap and refrigerate for 30 minutes. This helps the dough firm up and prevents the cookies from spreading too much while baking.

Bake the cookies: Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper. Scoop out rounded tablespoons of dough, roll into balls, and place them 2 inches apart on the sheet. Press a few extra chocolate chips on top of each dough ball for a bakery-style look. Bake for 11–12 minutes, until the edges are set but the centers are still soft.

Cool and serve: Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. Serve warm for melty chocolate bites or at room temperature for a chewy texture.