12 squares (1 ounce each) semisweet chocolate 
1 cup butter, softened 
1-1/3 cups plus 1/4 cup sugar, divided 
8 eggs
1 cup cake flour 
1/4 cup instant coffee granules or espresso powder
2 cartons (8 ounces each) Mascarpone cheese 
2 teaspoons vanilla extract 
1 teaspoon baking cocoa

In a large microwave-safe mixing bowl, melt chocolate.
Stir until smooth; cool slightly.
Beat in butter.
Gradually beat in 1-1/3 cups sugar.
Add six eggs, one at a time, beating well after each addition.
Combine the flour and instant coffee granules; add to the chocolate mixture.
Beat on low speed just until combined; set aside.
For filling, in a small mixing bowl, beat the cheese, vanilla, and remaining sugar and eggs until smooth.
Pour 4 cups of chocolate batter into a greased 13-in.x 9-in.x 2-in.baking pan.
Spread with the filling.
Top with the remaining batter, spreading evenly to completely cover filling.
Bake at 350° for 45-50 minutes or until center is almost set and brownies begin to pull away from sides of pan.
Cool on a wire rack.
Dust with cocoa.
Cut into squares.
Store in the refrigerator.