Line a large baking sheet with parchment paper.
Dust your workspace generously with flour and then transfer the dough to the workspace.
Divide the dough into 9-12 even sized pieces. (For large buns divide into 9 pieces or for smaller buns divide the dough into 12 pieces.)
Roll all the pieces of dough into a round ball, be sure all the balls are the same shape and size Add the baking sheet, separating about 2-3 inches apart from each other.
Cover lightly with a towel and let sit for 20 minutes.
Preheat the oven to 350°F.
Dust the bottom of a 1/4 measuring cup with flour. Press down into the center of each ball, creating an indent. (You can also pinch down with your fingers to create the indentation.)
Scoop or pipe the cream cheese filling into the center indentation of each bun, divide the cheesecake mixture evenly among all the buns. (I like to use my 2 Tbsp cookie scooper.)
Top the cream cheese mixture with blueberries, evenly dividing the berries between all the buns. (You can add more or less berries, depending on preference.)
With a pastry brush, brush the brioche buns with egg wash. (You do not want to brush the cream cheese filling, only the buns.)
Sprinkle the brioche border with streusel topping. (The streusel topping is optional.)
Bake at 350℉ for 20-23 minutes until the brioche buns are a light golden brown.
Remove and let cool for 10 minutes.
Top with powdered sugar or a simple sugar glaze and serve.