In one bowl, mix all the dry ingredients and half of the nuts.
In second bowl, mix all the wet ingredients. (If making the vegan version, mash the single banana and add to the wet ingredients.)
Cover bottom of baking dish with sliced bananas.
Sprinkle 1 cup of blueberries over the banana slices.
Sprinkle dry ingredients over banana and blueberries.
Pour wet ingredients over the top, shaking baking dish to distribute liquid all around.
Top with remaining blueberries and nuts.
Bake for 35-45 minutes until completely set and lightly browned on top.
Remove from oven and let sit for 5 minutes. Either cut into 8 square servings or scoop out with a large spoon.
Serve with warm maple syrup or extra fruit.
(The ingredients in the parentheses above are the substitutes to make the dish vegan. It is a bit 'banana-y' but not too bad. This is the version we generally make.)
I wish the baked blueberry oatmeal took a better picture! It just comes out so 'blue' from the blueberries popping when baked. Take my word for it that it tastes a heck of a lot better than it looks. We've actually started serving it in ramekins as it looks a lot better that way.