Fill a 2 qt pot halfway full of water, and bring it to a boil.

Add the pistachios, and boil for 3 minutes.

Strain the pistachios, then rub them with a clean kitchen towel to remove the skins. Set aside to dry.

Roughly chop 1/2 cup of pistachios, not the pistachios that you boiled, those are for the cream filling.

In a glass bowl, add 1 Tbsp oil, the white chocolate chips, and 1/4 c of the milk. Microwave in 30 second increments, stirring each time until melted.

In a blender, add the pistachios, salt, and the melted white chocolate mixture. Pulse until blended. Then, add 1/4 c of milk and blend, scraping as needed.

In a piping bag or large Ziploc bag, add the pistachio butter, trying to get the butter on one half of the piping bag.

Rinse out your blender. Add the ingredients for the whipped cream, and blend on high, checking every 20 seconds for the cream to be thick, but still creamy. It shouldn't drip off a spoon. But, don't blend too much, or it will turn to butter.

To the piping bag, add the whipped cream, pushing it on the empty half so that the bag is a blend of half cream/half butter. Alternately, you can fold the butter and cream together and place in bag. Cut the tip, and pipe the cream into the cooled cannoli shells. Garnish the ends with mini chocolate chips and sprinkle with powdered sugar.