Preheat the oven to 350 and lightly grease a muffin pan.
Unroll the Fillo dough (keep it stacked) and cut off a quarter of it. Cut it in half. Stack the two squares of Fillo sheets together. Using the butter spray, spray in between every 2-3 sheets. Grab 5-6 sheets at a time and carefully press them into the muffin cups, forming a cup out of the dough sheets. Bake the cups for about 8 minutes, until golden brown. Make sure to cool the cups completely before filling with cannoli cream.
While the cups are baking, make the cannoli cream. Beat the heavy cream and 2 tbs of sugar in a bowl with an electric mixer, until soft peaks appear. In a separate bowl, beat ricotta, sugar, vanilla and orange zest for a couple of minutes. Slowly, fold the ricotta mixture into the whipped heavy cream until all incorporated.
Scoop the cannoli cream into the cooled cups and sprinkle with mini chocolate chips.