Cut the puff pastry into large strips about 1-2 centimeters. Wrap each strip around support for cannoli then place the cannoli on a baking sheet. Brush them with egg yolk and milk and sprinkle with a pinch of salt. Bake at 180 degrees for 10 minutes until cannoli are golden and crispy. In a mixer, blend Mortadella Bologna PGI with ricotta and chives. Season with salt and chopped pistacchio. Transfer the mousse to a pastry bag. When the cannoli are completely cold, stuff them with the mousse and place them on a serving tray.