Preheat the oven to 350 F. Grease a 9"x13" pan and set aside.
In a medium saucepan melt the butter over low-medium heat. Add the sugar and stir to combine. Return the mixture to the heat and stir until the mixture is smooth and shiney; about 1 minute. Transfer the sugar mixture to a medium sized mixing bowl. Stir in the cocoa, baking powder, salt and vanilla extract.
Add in the eggs and stir until smooth. Add the flour and stir until flour disappears. Stir in the chocolate truffles. Spoon the batter into prepared pan. Gently place raspberries on top of the brownie batter.
Bake the brownies for 40-45 minutes, until a toothpick inserted into the centre comes out clean, or with just a few moist crumbs clinging to it. The brownies should feel set on the edges and the centre should look very moist, but not uncooked. Remove brownies from the oven and cool completely on a rack before cutting and serving.