In 2-quart heavy saucepan, mix brown sugar, cornstarch, coffee powder and salt. Add 2 cups of the whipping cream, the milk and egg yolks; stir with whisk until blended. Heat to boiling over medium heat; boil 1 minute until pudding thickens and coats back of spoon. Remove from heat.
Divide pudding evenly among 6 serving bowls or custard cups. Cover tops of pudding with plastic wrap to prevent skin from forming; refrigerate 2 hours or until chilled.
Just before serving, in chilled small bowl, beat remaining 1/2 cup whipping cream and the powdered sugar with electric mixer on high speed until stiff peaks form. Top each serving of pudding with whipped cream; sprinkle with cocoa.