How to Make It
Spray a 7- x 3-inch round cake pan with cooking spray, and line with parchment paper to fit the bottom; spray parchment with cooking spray. Prepare the brownie mix according to package directions. Stir in peppermint extract until combined. Pour batter into prepared cake pan.
Add 1 cup water to an Instant Pot. Place a trivet in the bottom of Instant Pot; using a foil sling, lower cake pan onto trivet. Lock the lid in place, position the pressure release to Sealing, select High Pressure and cook for 28 minutes. When cook time ends, carefully release the pressure, and turn Instant Pot off. Carefully remove lid, and remove cake pan using foil sling.
Allow cake to cool in pan on a wire rack for 1 hour. Use a knife to release sides of cake from pan, and carefully invert cake onto a serving platter. Remove parchment paper from surface of cake.
Place melting wafers in a small microwavable bowl, and microwave on HIGH for 30 to 45 seconds, stirring every 15 seconds until smooth. Spoon melted chocolate into a piping bag or a small ziplock plastic bag, and cut a very small hole in tip of bag; pipe a decorative pattern on top of cake. Sprinkle crushed candies and sprinkles on top of melted chocolate drizzle. Serve at room temperature or chilled.