1Heat oven to 350ºF. In medium bowl, mix 3/4 cup flour, the butter, powdered sugar and cocoa with spoon until soft dough forms. Press in ungreased square pan, 8x8x2 or 9x9x2 inches. Bake 10 minutes.
2In medium bowl, beat remaining ingredients except whipping cream and chocolate sprinkles with wire whisk until blended. Pour over baked layer. Bake 15 to 20 minutes or until filling is set. Cool slightly; refrigerate at least 2 hours before cutting. For bars, cut into 6 rows by 4 rows.
3In chilled small bowl, beat whipping cream with electric mixer on high speed until stiff peaks form. Spoon whipped cream into pastry bag fitted with medium writing or star tip. Pipe dollop of cream onto each bar. Top with chocolate sprinkles. Store covered in refrigerator up to 48 hours.