Step 1: Preheat your oven to 350°F (175°C) and grease a 9x13 inch baking pan or line it with parchment paper for easy removal.
Step 2: In a large bowl, whisk together the melted butter and sugar. Add eggs one at a time, followed by the vanilla extract, and whisk until smooth.
Step 3: Sift in the cocoa powder, flour, and salt. Fold the dry ingredients into the wet mixture until just combined, then stir in the chocolate chips.
Step 4: Pour the batter into the prepared pan and bake for 22-25 minutes. Let the brownies cool completely in the pan.
Step 5: While the brownies cool, melt the dark chocolate wafers in the microwave. Dip each sugar cone into the chocolate until fully coated. Place on wax paper to set.
Step 6: Once the brownies are cold, use a 3-inch round cutter to cut out 12 brownie circles. These will serve as the base for your wicked witch hat brownies.
Step 7: Tint your buttercream frosting with green food coloring. Pipe a thick ring of green frosting onto each brownie round.
Step 8: Press a chocolate-coated cone onto the center of each frosting ring. The frosting should squeeze out slightly to look like the ribbon on a hat. Add sprinkles for the buckle and enjoy!