Preheat oven to 180 C / Gas 4. Grease a 23cm square baking tin.
Combine cream cheese with 4 tablespoons sugar and 1 egg in a mixing bowl; beat until smooth. Stir chopped chocolate into the cream cheese mixture. Set aside.
Fill a small saucepan with water and bring to the boil. Turn the heat off, and set a large heatproof mixing bowl over the pan (the bowl should not touch the water). In the mixing bowl, combine butter with the remaining 170g of chocolate; stir until just melted and blended together. Stir in the remaining 100g sugar and 2 eggs, then sift together flour, baking powder and salt; stir into chocolate until evenly blended.
Pour half of the mixture into the prepared baking tin. Spread the cream cheese mixture over the chocolate layer. Top with remaining chocolate mixture (this doesn't need to completely cover the cream cheese layer). Using a knife, swirl the top chocolate layer into the cream cheese to make a marble pattern.
Bake in preheated oven at 180 C / Gas 4 for 25 to 30 minutes, or until top is crinkled and edges pull away from sides of the pan. Cool thoroughly. Cut into 12 to 16 squares. Store in the refrigerator or freeze.
When it said to use plain chocolate I bought baking chocolate with 72 % cocoa.. followed instructions, tasted it and it they were Gorgeous. So I couldn't wait for the rest of the family to taste them, but none of em liked it as it was "too dark" so they are now all mine Hahaha - 28 Feb 2011
Wonderful brownies, moist & sinful! Very easy to make, and probably the best recipe I've tried at home. I did a slight tweak though, and changed the 170gr of dark chocolate in the cheese & egg mix, to just 50gr of white chocolate, which was sweet enough and absolutely moreish! - 06 Nov 2013