Grease a 9x13 pan with cooking oil.
Place frozen rolls in the pan and cover with a towel let them rise 3-4 hours or follow package directions.
Fill your pot on the stove with enough oil to coat what you’re frying, about 4-6 cups.
Start with less and add more if you need to.
Heat until it reaches about 365 degrees, or if you don’t have a thermometer (I don’t) until a dribble of batter dropped on top sizzles and browns, I just pull off a tiny piece of the dough and try it out.
Fry for 3-4 minutes, while turning the dough every 30-seconds or so, to make sure to get a nice golden brown color evenly on both sides. I fry 6 at a time.
Remove donuts from the oil once completely cooked and let them cool and dry on a plate cover with a paper towel.
Once cooled, using a sharp bread knife. Cut a small "X" into the side of the roll, to make it easier to pipe the Nutella into the roll.
Using a Ziplock or a piping bag, add a frosting tip to the tip of the bag with the tip cut off, I used tip #804. Push the tip through so just the first half is coming out of the bag. Then fill the bad with Nutella, I used about 1 1/2 cups.
Push the tip of the piping bag into the "x" of the donut and pipe the Nutella into the donut, until the donut starts to slightly expand in your hand, you can pipe as much or as little as you would like into the center of the donuts. We like a lot.
Repeat with remaining donuts.
Add 2 tablespoons of Nutella to a small bowl and heat in the microwave for 1 minute. Stir it and then drizzle over the filled donuts. Sprinkle the chopped pistachios over the Nutella drizzle.
Serve. Take a bite. And devour.