Heat oven to 350. Line 9 inch baking pan with aluminum foil leaving 2 inch overhang on edges. Butter and flour foil; set aside.
Place 1 cup dark chocolate chips and butter in medium microwave-safe bowl. Microwave on high, stirring every 30 seconds ocasionally, or just until chips are melted. Stir until smooth.
Combine sugar and eggs in medium bowl. Beat at medium speed until thick and smooth. Add melted chocolate mixture; continue beating until smooth. Stir in flour and remaining 1/2 cup dark chocolate chips just until flour is mixed inches.
Spread batter into prepared pan. Bake for 30 to 35 minutes or until edges are set and center appears soft. Cool completely.
Meanwhile, place semisweet chocolate chips in a bowl. Place whipping cream in 2 quart saucepan. Cook over medium heat until whipping cream just comes to a boil. Pour warm cream over chocolate chips; let stand 1 minute. Stir until smooth. Cool 5 minutes. Spread over cooled bars.
Drop 8 small portions of melted white chocolate randomly over glaze. Pull knife through white chocolate to create design. Cover; refrigerate at least 2 hours or until serving time.
Carefully lift bars out of pan using foil overhang. Cut into bars using sharp knife.