Preheat oven to 370℉/180℃. Line a 8″ square baking tin with greaseproof paper.
Melt the dark/semi-sweet chocolate by breaking up into small pieces in a bowl and heating for 30 second intervals in a microwave, stirring in between. Set aside to cool whilst making the brownies.Alternatively, set up a double boiler. Do this by placing a heatproof bowl over a small pot of simmering water. Add the chocolate to the heatproof bowl and stir until melted. In a large bowl or the bowl of a stand mixer combine the melted butter, and both the brown and granulated sugars on a medium speed until fully combined. Add the eggs and vanilla and mix again. Add the melted chocolate.
Add in the flour, cocoa powder, ginger and cinnamon and fold together. Pour the batter into the prepared pan.