Preheat oven to 350°F (180°C). Butter a 9 x 9-inch square baking pan.
Combine 1 cup sugar and next 4 ingredients in a bowl. Add 3 tbsp. cocoa. Combine milk, butter, vanilla and melted chocolate in another bowl and mix thoroughly. Add to dry ingredients and beat with an electric mixer until well blended. Pour batter into prepared 9 x 9-inch square baking pan and set aside. Combine remaining sugar, brown sugar and remaining cocoa in a mixing bowl. Slowly whisk in hot water. Whisk until smooth. Gently ladle sauce over cake batter to cover completely. Bake 35-40 minutes or until a tester comes out clean when inserted in center.
Makes 8 servings.
Date: April 16, 2004