In a small pot, combine the ingredients listed for Tangzhong.

Heat the mixture over medium heat, stirring continuously.

Once the mixture thickens to a pudding-like consistency, remove it from the heat.

Transfer the tangzhong to a bowl and cover it with plastic wrap that touches the surface of the tangzhong. This is to prevent a skin from forming.

Allow the tangzhong to cool to room temperature before continuing with the next step.

In the bowl of a stand mixer fitted with a dough hook, combine all the ingredients listed for the main dough, including the tangzhong.

Knead the dough on low to medium speed for about 10 minutes.

Gradually add the cubed butter to the dough, one cube at a time, while continuing to knead.

Continue kneading for another 10-20 minutes or until the dough passes the window-pane test - it should be smooth, elastic, and able to be stretched thinly without tearing.

Transfer the dough to a clean, lightly oiled bowl.

Cover the bowl with plastic wrap and let the dough proof for about 90 minutes, ideally at around 77 °F (25°C), until it doubles in size.

In a pot, combine the ingredients listed for the blueberry filling.

Simmer the mixture over medium-low heat until it thickens to a jam-like consistency.

Stir occasionally and mash the blueberries with your spatula as they cook. The filling should become thick and cohesive. It's important to let it simmer until it reaches this point. You can test it by tracing a line with your spatula along the bottom of the pot—when it's thick enough, the line should stay visible for at least a few seconds.

Allow the blueberry filling to cool to room temperature.

Optional: For an even smoother blueberry filling, press it through a fine mesh sieve with the back of a metal spoon, ensuring you extract all the filling and leave only the seeds behind in the sieve.

Preheat the oven to 350°F (180°C).

Roll out the proofed dough on a lightly floured surface into a rectangle measuring approximately 16x16 inches (40x40 cm).

Evenly spread the cooled blueberry filling over the dough.

Starting from one edge, tightly roll up the dough into a log.

Using dental floss or a sharp knife, slice the log into 9 even pieces.

Arrange the rolls in a greased 9x9-inch (23x23 cm) baking pan.

Cover the baking pan with plastic wrap and allow the rolls to proof for 30-45 minutes, ideally at around 77 °F (25°C).

Bake the rolls in the preheated oven for 25-30 minutes or until the internal temperature reaches 200°F (95°C).

Using a hand mixer, whip together the cream cheese and butter until light and fluffy, which should take about 5 minutes.

Gradually add the powdered sugar and vanilla paste to the cream cheese mixture, continuing to whip until smooth and fluffy. In the end, mix in a tiny pinch of salt to balance the sweetness of the cream cheese frosting.

Once the blueberry rolls have cooled slightly, drizzle the frosting over the top of the rolls.

Serve and enjoy!