01 -
Preheat oven to 350°F. Line 8x8 inch baking pan with parchment paper.
02 -
Microwave butter and chopped chocolate in 30-second increments until melted, stirring between each.
03 -
Stir in sugar, then eggs one at a time. Add vanilla, vinegar, and food coloring.
04 -
Sift together cocoa, flour, and salt. Gradually mix into wet ingredients just until combined.
05 -
Pour into prepared pan. Bake 30-35 minutes until toothpick comes out with few moist crumbs.
06 -
Cool completely. Optional: drizzle with melted white chocolate. Cut into squares.