Place the chocolate and butter in a bowl over a pan of simmering water. Gently stir until melted and remove from the heat once melted.
Pre-heat the oven to 350F/180C degrees.
Grease and line a baking tin with greaseproof paper (I used a 8 inch square tin)
Place the cheesecake ingredients in a bowl and mix well under smooth.
Add the eggs and vanilla to the melted chocolate and butter mixture and blend well.
In another bowl, add the remaining dry ingredients and stir to mix.
Pour the chocolate mixture into the dry ingredients and mix.
Spoon the chocolate mixture into the cake tin.
Pour the cheesecake mixture on top of the chocolate mixture in the cake tin.
With a knife, place it into the mixture and swirl, blending the two mixtures. (It should leave a swirl patter).
Place in the oven and bake for 30 minutes.
Let cool at room temperature, then place in the fridge for at least 2 hours.
Eat and enjoy!