In a large mixing bowl, combine warm milk, active dry yeast, and granulated sugar. Allow this mixture to sit for 5 minutes until it becomes frothy.

Add melted unsalted butter, beaten egg, salt, and all-purpose flour to the bowl. Mix until a soft dough forms.

Turn the dough out onto a floured surface, kneading it for about 5-6 minutes until smooth and elastic.

Place the kneaded dough in a greased bowl, cover it, and let it rise for about 20 minutes, until doubled in size.

Mix together brown sugar and ground cinnamon in a small bowl and set aside.

Punch down the dough, turn it onto a floured surface, and roll it into a rectangle approximately 12x16 inches.

Spread softened butter over the rolled-out dough and sprinkle the cinnamon-sugar mixture generously over it.

Starting from the long edge, tightly roll the dough into a log and slice it into 8 equal pieces.

Let the rolls rise for an additional 15 minutes while preheating your oven to 350°F.

Bake the rolls for 18-22 minutes until golden brown and centers feel firm.

Prepare the glaze by whisking together powdered sugar, vanilla extract, and heavy cream or milk until smooth.

Allow the rolls to cool for a few minutes before drizzling the glaze over them and serve warm.