Preheat oven to 375°F (190°C). Lightly grease a standard 12-cup muffin tin.
Cut each wonton wrapper into quarters. Brush both sides of each wonton piece with melted butter. Press 2-3 buttered wonton pieces into each muffin cup, overlapping slightly to form a cup shape.
Bake for 8-10 minutes, or until golden brown and crispy. Let cool in the muffin tin for a few minutes before carefully removing them to a wire rack to cool completely.
In a medium bowl, combine the drained ricotta cheese, powdered sugar, and vanilla extract. Mix until smooth and well combined.
Gently fold in the mini chocolate chips.
Spoon or pipe the ricotta filling into the cooled cannoli cups. Garnish with chopped candied orange peel or pistachios, if desired.
Chill for at least 30 minutes before serving to allow the filling to set.
Notes
These cannoli cups are best enjoyed the same day they are made. If making ahead, store the crispy cups separately and fill them just before serving to prevent them from becoming soggy.