Chocolate and orange brownie cake

125g dark chocolate, broken into pieces

170g caster sugar

70g muscovado sugar

100g butter, softened

2 eggs, beaten until fluffy

100g plain flour

zest of 2 oranges

½ tsp baking powder

2 tbsp cocoa powder

small handful of candied orange peel, chopped

To decorate:

50ml cream

50g dark chocolate, broken into small chips

handful of candied orange peel strips