Pre-heat oven to 180°C (160°C fan-forced). Line a 20 x 30cm baking tray with baking paper. Place chocolate, butter and sugar in a pan and gently melt over low heat, stirring occasionally with a wooden spoon. Remove from heat.
Stir the eggs into the melted chocolate mixture, one by one. Add flour and cocoa, and mix well. Stir raisins through mixture.
Spread out evenly in prepared baking tray and bake for 30 minutes. Allow to cool.
Place the brownie on a clean work surface. Use a large serrated knife to trim outside edges of brownie. Cut in half. Cut each half into 6 triangles, about 10cm long and 6cm wide.
Gently insert star toothpick on top and candy cane (or timber skewer) on the bottom as a tree trunk. Decorate with white melted chocolate and red Smarties.