1Heat the oven to 175 C and line a 9 inch square tin.
2Brownie: melt 120 g chocolate with 100 g butter. Whisk with 150 g sugar and 2 eggs, then fold in cocoa and 60 g maida. Spread in the tin.
3Cookie: cream the remaining butter with brown sugar and the remaining sugar, beat in the last egg and vanilla, then mix in the remaining maida, soda, salt and the rest of the chocolate, chopped.
4Dot the cookie dough over the brownie and gently press flat.
5Bake 30 to 35 minutes and cool completely before cutting.
Serve it like this
Cut into squares to show both layers and serve with cold milk or a scoop of ice cream.