Warm the milk until just lukewarm and sprinkle the yeast over the surface; let it sit until foamy.

Whisk in the egg and softened butter.

In a separate bowl, combine flour, granulated sugar, and salt, then add to the wet ingredients and knead until the dough is smooth and elastic — about 6–8 minutes by hand or 4–5 minutes in a stand mixer.

Place the dough in an oiled bowl, turn to coat, cover with a clean towel or plastic wrap, and let rise in a warm spot until doubled in size, roughly 1–1.5 hours.

Stir pistachio butter or pistachio cream with brown sugar and ground cinnamon until it forms a spreadable paste.

On a lightly floured surface, roll the dough into a rectangle.

Spread the pistachio filling evenly over the dough, leaving a small border at the edges.

Roll tightly from the long side and slice into even rolls using a sharp knife or unflavored dental floss.

Arrange the rolls in a greased small pan (9-inch round or similar), spacing them slightly.

Cover and let rise until puffy and nearly doubled — about 30–45 minutes.

Preheat your oven to 350°F (175°C).

Bake the rolls for 23–30 minutes, until the tops are golden and the centers are set but still soft.

Whip softened cream cheese with powdered sugar, a splash of vanilla, and heavy cream until smooth and spreadable.

Stir in a spoonful of pistachio butter for color and depth, adjusting thickness with more powdered sugar or cream as needed.

Spread the icing over warm rolls so it melts into the swirls.

Garnish with chopped pistachios if desired and serve while still warm.