Whip cream to soft peaks and add sugar-beat to combine.
Spread over pastry cream and chill.
Once cold, drizzle on the cooled chocolate and store in fridge.
To prepare sweetened whipped cream
In a large mixing bowl, using an electric hand mixer, whip 3/4 cup heavy cream until soft peaks form. Add in granulated sugar and whip until stiff peaks form. Spread sweetened whipped cream evenly over pastry cream layer.
Cut pie into slices and drizzle each slice with cooled chocolate sauce. Serve immediately. Note: this pie is best served the day prepared. Also note, the sweetened whipped cream will begin to separate after about 3 hours so plan accordingly. Store in refrigerator in an airtight container.