preheatoven to 350 degrees F ( 180 degree C ) and place the rack in the center of the oven. butter or spray with a nonstick cooking spray. an 8 inches (20cm) square pan, and line the bottom of the pan with baking paper.
1
melt the chocolate chips and the butter in a large stainless bowl.placed over a saucepan of simmering water.Remove from the heat and stir the cocoa powder and sugar .next whisk in the vanilla extract and eggs ,one at a time, beating well after each additional . finally stir in the flour.
2
pour into the prepared pan and bake for about 30 minutes, or until a toothpick inserted in the center comes out with a little batter and a few moist clumps clinging to it. Do not over bake.
3
remove from oven and let cool on a wire rack . serve at room temperature or chilled . these freeze very well.