In a medium bowl, combine packed light brown sugar, matcha powder, ground cinnamon, and fine salt. Stir until fully blended and set aside.

In a large mixing bowl, mix all-purpose flour, matcha powder, instant dry yeast, and fine salt. In a microwave-safe container, heat whole milk and unsalted butter until melted. Pour into dry ingredients, mixing until a shaggy dough forms.

Add the large eggs one at a time, stirring well after each addition until the dough is sticky. Gradually add more flour as necessary until the dough pulls away from the bowl.

Transfer the dough onto a floured surface and knead for 5-7 minutes until smooth and elastic. Place it in a greased bowl, cover with plastic wrap, and let it rest in a warm spot for 10-20 minutes.

Roll the rested dough into a large rectangle, about 14" by 18". Spread a layer of softened unsalted butter over it and sprinkle the matcha filling mixture evenly across.

Starting from one edge, tightly roll the dough into a log. Cut into 12 equal pieces and arrange in a greased baking pan.

Cover with a kitchen towel and let the rolls rise in a warm area for 30-45 minutes until double in size.

Preheat the oven to 350°F (175°C). Bake rolls for 28-32 minutes until golden brown. Enjoy the aroma of baking.

Combine cream cheese, vanilla extract, powdered sugar, and whole milk in a mixing bowl. Beat until smooth. Optionally reserve some frosting to mix with matcha powder.

Cool the rolls for 10 minutes, then drizzle frosting over them, allowing it to melt slightly into the rolls.