Preheat the oven to 375°F (190°C) and grease a baking dish.

In a mixing bowl, combine flour, sugar, baking powder, and salt.

Cut in the softened butter until the mixture resembles coarse crumbs.

In another bowl, whisk together milk, egg, and vanilla.

Add the wet ingredients to the dry mix and stir until just combined.

On a floured surface, roll out the dough into a rectangle about 1/4 inch thick.

Spread the dough with softened butter, sprinkle with cinnamon, and scatter the blueberries evenly over the top.

Roll the dough tightly into a log and cut into rolls.

Place the rolls in the prepared baking dish and bake for 20-25 minutes until golden.

For the glaze, mix powdered sugar with 2 tablespoons of milk until smooth.

Drizzle the glaze over the warm rolls before serving.