Preheat the oven to 200C/180C Fan/Gas 6. Line an 8" Square Pan.
Start by melting the dark chocolate: break up the dark chocolate and melt in the microwave in 20 second intervals, stirring in between to make sure it doesn’t burn. Set aside to cool a little whilst doing the rest:
Combine the melted butter, granulated sugar and light brown sugar in a large bowl/bowl of a stand mixer – on a medium speed for 3-5 minutes.
Add in the eggs and vanilla and mix again. Then, add the melted chocolate and stir to combine. Add flour and cocoa powder, fold in.
Stir in the add-ins: chopped chocolate, chopped almonds and berries.
Pour the batter into the lined tin. Bake 30 minutes. Let cool.
Finally, for optional decoration, melt the milk chocolate and drizzle over with a spoon. Add some crushed almonds, slice and serve!