Preheat the oven to 170°c (150 °fan/ Gas 3/ 325 °F) and line a 20 x 30cm baking tin with non-stick baking paper.
Place the butter and dark chocolate in a microwaveable bowl and melt in the microwave in 30 second bursts. Allow to cool.
200 g Butter, 200 g Dark Chocolate
Place the eggs in a large bowl and use an electric whisk to whisk for 2-3 minutes until light and fluffy.
3 Eggs
Add the brown sugar to the eggs and whisk for another minute.
250 g Light Brown Sugar
Mix the cooled melted chocolate mixture into the eggs mixture and stir to combine.
Gently mix in the flour and cocoa powder.
100 g Self Raising Flour, 30 g Cocoa Powder
Fold in the chopped chocolate orange and orange zest.
157 g Terry's Chocolate Orange, 1 Orange
Pour the mixture into the prepared tin and bake for 30-35 minutes until just set. Allow to cool in the tin.
Melt the dark chocolate for the topping and smear a little on the back of each chocolate orange minis segment before placing on top of the baked brownies.
50 g Dark Chocolate, 12 Chocolate Orange Minis
Use a sharp knife to cut into bars.