In a large mixing bowl, combine flour, sugar, and yeast.
Add warm milk, melted butter, egg, and salt, then knead until a soft dough forms.
Cover and let the dough rise in a warm place for about 1 hour, or until doubled in size.
Roll out the dough into a rectangle and spread softened butter over it.
Mix brown sugar and cinnamon, then sprinkle evenly over the buttered dough.
Scatter fresh blueberries on top.
Roll up the dough tightly, then slice into rolls.
Place rolls in a greased baking dish and let rise for another 30 minutes.
Bake at 375°F (190°C) for 20-25 minutes, until golden brown.
Mix powdered sugar, milk, and vanilla extract to make the glaze, then drizzle over warm rolls before serving.