Starbuck's blueberry bar - copycat from relish.com, from foodlibrarian.com and Food.com ........

I microwave the filling, make sure to mix the sugar and cornstarch to prevent lumping.

Bring to a complete boil.  High level stirring every 2 minutes.

Add all dry ingredients to a bowl (I placed the bowl in my glass baking dish to avoid making a mess)

I use the lines on the butter pack to measure accurately.

Use a large grater instead of a pastry blender/cutter. Again, thank you Alton Brown

My butter was very hard, right out of the fridge.  Stir into dry ingredients as you grate. You want the butter  coated
with flour. 

Make sure the butter in mixed in evenly.

I greased the pan with the butter wrapper, just like my Mom used to!!

Reserve 1/2 of the crumbs for the top crust. Press down with the measuring cup (careful not to snap off the handle)

Play connect the dots with the filling - it prevents the bottom layer from pulling up! 

Smooth out the filling (connect the dots).

Sprinkle the filling with the topping.

Pat down the topping, gently.  I used a different measuring cup this time.  BAKE