Preheat oven to 350 degrees. Line a 9x9 pan with parchment paper.
Combine milk and vinegar and set aside.
In a large bowl, combine flour, cocoa powder, salt, baking powder and sugars. Stir well.
In a second bowl, crack the eggs and whisk until frothy. Add the oil, vanilla and food coloring. Stir well. Pour the wet into the dry. Add the milk. Fold together until all the dry ingredients are incorporated. Fold in the dark chocolate chips.
Pour the batter into the prepared pan and bake in preheated oven for 25 minutes.
Remove from oven to cool.
Once completely cooled, drizzle the top with the melted white chocolate, if you like.
Store in an airtight container…or eat them all in one sitting 😉