Beat together the cheese, 50 g sugar and 1/2 tsp. vanilla until smooth, then set aside.
Preheat the oven to gas mark 4.
Lightly grease a 20cm-8inch square baking tin and line the base.
Sift the flour, cocoa powder and baking powder and keep aside in a mixing bowl.Now combine yogurt, remaining sugar and vanilla and leave it aside.Place dark chocolate in a heatproof bowl, either use M/W to melt or use double boiler method
Add melted chocolate and yogurt mixture and combine well.
Add chocolate and yogurt mixture into sifted flour mix.
Add nuts mix.
Pour the half brownie batter into a greased and lined baking tin and smooth the top.Carefully spread the cheese mixture over it, then cover it with the remaining brownie mixture.Use a palette knife to swirl the two mixtures together gentl
Bake it for 55-60 minutes, yes it takes that much time.
Remove it from the oven, let it cool and cut into pieces.
Serve it with a cuppa or dust little icing sugar and strawberries.