Warm the milk until lukewarm, about 100°F (38°C). Combine warm milk with yeast and let sit for 5-10 minutes until frothy.

Whisk in the egg and melted butter. Gradually add flour, sugar, and salt, mixing until a sticky dough forms.

Knead on medium speed for about 5 minutes until smooth.

Transfer the dough to a greased bowl, cover with a towel, and let rise in a warm area for about 1 hour.

Prepare the pistachio filling by mixing pistachio butter, brown sugar, and cinnamon in a bowl.

Once dough has risen, roll it out into a 12x9 inch rectangle and spread the filling over it.

Tightly roll the dough into a log and slice into 4-6 equal rolls.

Place the sliced rolls in a greased baking dish, cover, and let rise for 30-45 minutes.

Preheat oven to 350°F (175°C) and bake rolls for 23-30 minutes, until golden brown.

Prepare the icing by whipping together cream cheese, powdered sugar, vanilla extract, and pistachio butter until smooth.

Once the rolls cool slightly, spread the icing generously over them and serve.