Preheat & Prepare: Preheat your oven to 350°F (175°C). Line an 8×8-inch baking pan with parchment paper, leaving overhang on the sides for easy lifting.
Make Brownie Batter: In a large bowl, whisk together melted butter, sugar, eggs, and vanilla until glossy. Add flour, cocoa powder, and salt; stir until just combined.
Bake: Spread the batter evenly in the pan and bake for 20–25 minutes, or until the center is just set. Don’t overbake.
Cool Completely: Allow the brownies to cool in the pan for 20 minutes, then transfer the whole slab to a wire rack to cool fully before topping.
Melt White Chocolate: In a microwave-safe bowl or double boiler, gently melt the white chocolate until smooth. Stir in peppermint extract.
Top with Peppermint: Pour melted white chocolate over the cooled brownies, spreading evenly to the edges. Immediately sprinkle crushed candy canes on top.
Chill: Refrigerate for 15–20 minutes, or until the white chocolate is firm.
Slice & Serve: Lift the brownies out of the pan using the parchment. Slice into squares with a sharp, warm knife for clean edges. Enjoy!