In a small bowl, warm the milk until lukewarm, then sprinkle the yeast over it. Let it sit for about 5 minutes until foamy.

In a mixing bowl, combine the egg and softened butter, then mix in the yeast mixture.

Gradually add the flour, sugar, and salt, stirring until a soft, sticky dough forms.

Transfer the dough to a lightly oiled bowl, turning it to coat all sides. Cover and let it rise for about 1 hour.

Mix together the pistachio butter, brown sugar, and ground cinnamon until evenly combined to prepare the filling.

Roll the dough into a rectangular shape and spread the pistachio filling evenly over it.

Tightly roll the dough into a log and slice it into 4 to 6 equal pieces.

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

Preheat your oven to 350°F, then bake the rolls for 23-30 minutes until golden brown.

Prepare the icing by mixing cream cheese, powdered sugar, vanilla extract, and heavy cream until smooth.

Spread the icing generously over the rolls once cooled slightly and serve warm.