Super easy, it's only 4 simple steps. Here is a photo tutorial to show you just how easy it is.
Step 1: The filling.
Boil and simmer some blueberries, sugar and orange juice. Whisk in cornstarch. Refrigerate.
Stir oats, flour, brown sugar, salt and baking soda. Cut in butter.
Voila. Deliciousness. Just as good as Starbucks. :)