In a large bowl, whip together amaretto, cinnamon, heavy cream and confectioners' sugar until soft peaks form.
In a medium bowl, combine the pistachios and ricotta and stir in half of the whipped cream. Gently fold in the remaining whipped cream. Fill a pastry bag with no tip with the mixture to fill the cannoli shells.
Dip the tips of the cannoli into the melted chocolate. Place the sheet tray in the refrigerator for 2 hours or until filling and chocolate is set.