Preheat oven to 325 degrees. Prepare baking pan by lightly greasing or lining with parchment paper.
Combine water, oil, and egg in a mixing bowl. Add brownie mix and peppermint extract; stir until fully combined. Spread into pan.
Bake for 45-50 minutes.
Once brownies have cooled drizzle with white chocolate and sprinkle peppermint crunch baking chips on top.