Preheat the oven to 375 degrees. Spray an 8x8 inch baking dish with nonstick spray.
In a large mixing bowl, add the oats, pecans, baking powder, salt, and cinnamon. Use a wooden spoon to mix it all together.
In a smaller mixing bowl, add the egg, maple syrup, milk, and vanilla extract. Whisk to combine.
Pour the wet ingredients into the oat mixture, use the spoon to stir until combined. Then add the blueberries and gently stir until combined, be gentle to not crush the berries.
Pour the mixture into the baking dish and bake for 25-30 minutes. The top should be slightly brown and the oats firm in the middle.
This can be eaten hot or cold. When ready to serve add peanut butter or any other toppings you want!