Melt 2 Ounces of the Chocolate. Set aside to cool slightly.
Crush the large cannoli shell into coarse pieces and mix with half of the chopped pistachios. Place the mixture on a plate.
Spread the melted chocolate around the rim of the 2 (10-12) ounce glasses and about 1 inch down from the rim on the outside. Cover the chocolate in the crushed shell and pistachios.
Coarsely chop the remaining 1 ounce of chocolate.
Place the ice cream, drained ricotta cheese, heavy cream, powdered sugar, orange zest and half of the chopped chocolate in a blender and mix until the ingredients are completely blended.
The mixture will be thick and you might need to use a tamper to get it blending. If your blender does not have a tamper, stop it occasionally and mix it with a spatula and blend again. Don’t be tempted to add additional cream or milk or your milkshake will have a thin consistency.
Pour the shake into the prepared glasses and garnish with whipped cream, chopped pistachios, chocolate and the mini cannoli.
Serve Immediately and Enjoy!!