In a large mixing bowl, combine all-purpose flour, granulated sugar, and salt. Create a well in the center and pour in warm milk, melted butter, and beaten eggs, along with the vanilla extract. Mix until a soft dough forms.

Turn the dough out onto a floured surface and knead for 5-7 minutes until smooth and elastic. Shape into a ball, place in a greased bowl, cover, and let rise for about 1 hour, or until doubled.

Mix brown sugar and ground cinnamon in a small bowl to prepare the filling.

After dough has risen, punch it down and roll it out to a rectangle, 1/4 inch thick. Brush with melted butter and sprinkle the cinnamon mixture evenly over the surface.

Roll the dough tightly into a log and slice into 12 pieces. Arrange in a tree shape on a parchment-lined baking sheet. Cover and let rise for another 30 minutes.

Preheat oven to 350°F (175°C). Bake rolls for 20-25 minutes until golden brown.

Allow rolls to cool slightly, then whisk powdered sugar with milk to create icing. Drizzle over warm rolls and decorate as desired before serving.