01 - Preheat oven to 350°F. Line an 8x8 inch baking pan with parchment paper.
02 - In a microwave-safe bowl, melt butter and chocolate chips in 30-second intervals, stirring until smooth. Allow to cool slightly.
03 - Whisk in sugar, eggs, vanilla extract, and peppermint extract until mixture is glossy.
04 - Gently fold in gluten-free flour blend and salt until just combined.
05 - Pour batter into prepared pan and smooth the top evenly.
06 - Bake for 22 to 25 minutes or until a toothpick inserted in the center comes out with moist crumbs. Let cool completely in the pan.
07 - Beat softened butter until creamy. Gradually add powdered sugar, then milk and peppermint extract, beating until fluffy.
08 - Optionally, stir in red food coloring to create a pink swirl effect in the frosting.
09 - Spread frosting evenly over cooled brownies and sprinkle crushed peppermint candy canes on top.
10 - Cut into 12 squares and serve.