Preheat oven to 375 degrees F.
Add 2 cups of blueberries to the bottom of a 11x11 square baking dish (or a 9x13).
In a small bowl, mix together oatmeal, baking powder, sea salt, and cinnamon. Mix well, and then sprinkle over blueberries in baking dish.
Using the same bowl, mash bananas. The more ripe your bananas are, the sweeter your oatmeal will be. If your family prefers sweetened oatmeal, you can add 2-3 tablespoons of the sweetener of choice in with the banana.
Add eggs, almond milk, and coconut oil to the bananas, and stir together. Pour over the oatmeal mixture in the baking dish.
Top with reserved 1/2 cup blueberries, and sprinkle with pecans and pumpkin seeds, or other desired nut or seed.
Bake for 40-45 minutes.
Serve hot, and drizzle with honey or maple syrup, if desired.
Baked oatmeal can be stored in the refrigerator for up to 4 days, or frozen in an airtight container for up to a couple of months. Reheat individual portions as needed.