Preheat the oven to 325℉. Coat the inside of a 9x5 inch loaf pan with cooking spray and line it with parchment paper.
In a bowl, add in the all purpose flour, baking soda, baking powder, cinnamon, and salt. Whisk the ingredients together to remove any lumps and until the ingredients are evenly distributed.
In a separate large bowl, add in the eggs, brown sugar, and granulated sugar. Whisk the ingredients together until well combined and it turns a light brown color. Then mix in the maple syrup, maple extract, vanilla extract, vegetable oil, and buttermilk until incorporated. Pour half of the batter into the prepared loaf pan.
In another bowl, add in the blueberries and cornstarch. Toss the blueberries and cornstarch together until the blueberries are evenly coated with the cornstarch. Add this to the remaining half of the batter and gently fold them together until the blueberries are evenly distributed throughout. Pour the batter into the pan.
Place the loaf pan on top of a baking sheet to catch any potential spills, then bake it in the oven for 30 minutes. After 30 minutes, gently open the oven door and pull out the oven rack so you can reach the pan. Quickly distribute the crumble topping all over the top of the bread. Move the pan back into the oven and bake for another 45 minutes until the bread is cooked and a toothpick inserted comes out clean.
Remove the bread from the oven. Allow it to cool in the pan for 20 minutes before lifting it out and transferring it to a wire rack to continue cooling. Slice and enjoy!