01 -
Line or grease an 8x8 inch baking pan with parchment paper, leaving an overhang for easy removal.
02 -
In a microwave-safe bowl, melt butter and chopped chocolate in 30-second intervals, stirring until smooth and glossy.
03 -
Whisk sugar into the warm chocolate-butter mixture until blended. Beat in eggs one at a time, then stir in vanilla, vinegar, and food coloring until evenly mixed.
04 -
Sift cocoa powder, flour, and salt into a bowl to remove lumps and aerate.
05 -
Fold dry ingredients gently into wet mixture until just combined, avoiding overmixing.
06 -
Fold in white chocolate chips or nuts if using, mixing lightly for even distribution.
07 -
Spread batter evenly in prepared pan. Bake until a toothpick inserted in the center comes out with a few moist crumbs, about 25–30 minutes.
08 -
Allow brownies to cool fully in the pan, then lift with parchment and cut into squares with a sharp knife.