Cook pudding according to package direction, using the 3 cups milk. Remove from heat, add chocolate and stir until melted. Stir in malted milk powder. Cool mixture 5 minutes, stirrin often, then pour into crumb crust. Cover and refrigerate at least 2 hours.
Up to 1 hour before serving: Beat cream and sugar with electric mixer until soft peaks form when beaters are lifted. Spread cream over chocolate filling. Sprinkle with the chopped malted milk balls and drizzle with chocolate syrup. Refrigerate until serving time.