Instructions

1. In a large bowl combine 2 cups of the flour, yeast, salt and sugar in a bowl. Mix to combine.
2. In a microwave safe bowl, microwave the milk and butter for 30 seconds until warm and the butter is mostly melted. The mixture should be warm, but not hot. If it is too hot, make sure to let it cool before adding to the yeast to prevent killing the yeast. Add the warm milk and butter to the flour mixture.
3. Add the egg.
4. Beat on low speed, gradually increasing to high until completely combined, about 2 minutes.
5. Scrape down the bowl and add 1 more cup of flour, beating until combined. Add the remaining cup of flour in a little at a time until the dough starts to pull away from the sides of the bowl and form a ball. If the dough still feels wet, add the additional 1/2 cup flour!
6. Turn the dough out onto a well floured surface and knead for about 10 minutes until smooth and you can stretch a piece of dough out between your fingers without it breaking. This means the gluten has developed and your dough will be pillowy soft.
7. Transfer the dough to an oiled bowl and cover. Let rise in a warm place for 1 hour or until the dough has doubled in size.
8. While the dough rises, make the filling. In a food processor or high powered blender, pulse the pistachios until they break down into fine crumbs. Add the melted butter, granulated sugar, honey, orange zest, water and orange blossom water (if using) and pulse until the mixture comes together and forms a smooth, spreadable paste. You may need to add an extra tablespoon of water to get it to a spreadable consistency!
9. Once the dough has risen, roll it out into a long rectangle about 18 x 12 inches on a well floured surface.
   Spread the filling all the way to the edge of the dough.
10. From the long end, roll the dough away from you into a tight roll, sealing the bottom edge down by pinching the dough together.
11. Use floss or a very sharp knife to cut the dough into 12 even rolls. Place the rolls in a 9 x 13 inch pan lined with parchment paper. Cover loosely with a dish cloth and allow to rise for another hour until doubled in size and puffed up.
12. Bake the rolls at 350°F for 30 minutes or until they are golden brown and no longer doughy. Allow to cool.
13. While the rolls cool, make the frosting. In a mixing bowl combine the powdered sugar, butter, milk, vanilla and salt. Whisk together until smooth. Drizzle the icing all over the 12 rolls. Enjoy warm!