Preheat oven to 350 degrees. Line 48 mini muffin tins with paper liners and set side.
Melt butter and chocolate together in microwave. Stir in sugar and cocoa. Stir in eggs and vanilla. Stir in all dry ingredients. Spoon into prepared pan to fill 2/3 way. Unwrap Mint Truffle kisses and press 1 into each brownie bite. Bake 10-12 minutes or until brownie is thoroughly cooked. Cool completely.
For the frosting, whip all ingredients together in a large stand mixer until smooth and creamy. Frost the tops of each brownie bite and add a piece of mint truffle kiss to each one as decoration. Serve.