1. Preheat oven to 180°C. Grease a 20cm square cake tin and line the base with baking paper.
2. Place the brownie mix, butter, eggs and water into a medium mixing bowl. Mix with a wooden spoon until well combined and smooth.
3. Spread the mixture in the prepared tin and bake for 30-35 minutes or until a skewer inserted into the middle comes out clean. Let cool completely in tin.
4. Make the chocolate icing by placing the frosting mix, butter and milk into a small mixing bowl. Using an electric mixer beat on low speed for 30 seconds to combine. Increase speed to high and mix for 3 minutes scraping down the side of the bowl occasionally. Remove the brownie slice from the tin and spread over the icing.
5. Once the icing has set cut the brownie slice into 10 triangle shapes. Mix the icing sugar with the water to a drizzling consistency, adding more water if necessary, then drizzle over the brownies and place on chocolate candies for baubles.