01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - Whisk together flour, cocoa powder, baking soda, and salt in a medium bowl.
03 - Beat butter, granulated sugar, and brown sugar until light and fluffy.
04 - Add eggs one at a time, beating well after each. Mix in milk, vanilla, vinegar, and food coloring.
05 - Gradually add dry ingredients to wet, mixing until just combined.
06 - Gently fold white chocolate chips into the dough.
07 - Scoop tablespoon-sized dough balls onto prepared sheets, spacing 2 inches apart.
08 - Bake 10–12 minutes until edges are set but centers remain soft.
09 - Let cookies rest on baking sheet 5 minutes, then transfer to wire rack to cool.