In a bowl combine the blueberries with the sugar and mix.
Keep the blueberries aside to marinate a bit.
In another mixing bowl add the flour, baking powder, salt, butter, and milk. Combine to a smooth batter.
Preheat your oven to 350° Fahrenheit/ 180° Celsius.
Keep a casserole baking dish ready and place the blueberries marinated in sugar into the dish, spread out evenly.
Pour the batter over the blueberries and spread it out evenly as well.
Sprinkle sugar all over the unbaked cobbler.
Bake cobbler for about 40 minutes at 350° Fahrenheit/ 180° Celsius or until you can see the fruits bubbling up at the sides and the batter is baked amber golden brown.
Video
Notes
you can use frozen blueberries too. Just thaw them first.
you can freeze your cobbler too by preparing everything, freezing, defrosting when you need it and baking your cobbler. See instructions in post further above.