Preheat your oven to 350°F. Spray a 9x5 loaf pan with nonstick spray.

In a small bowl, whisk together the flour, baking powder, cinnamon, baking soda, and salt.

In a large bowl, use an electric mixer to beat the butter and sugar until they're light and fluffy.

Beat in the eggs and vanilla extract until everything is well combined.

Mix in the mashed bananas by hand, scraping down the bowl as needed.

Gently stir in the dry ingredients, making sure not to overmix the batter.

Fold in the blueberries until evenly distributed.

Pour the batter into the prepared loaf pan and bake for about 1 hour, or until a tester inserted into the center comes out clean. If the bread starts to brown too much, tent it with aluminum foil towards the end of baking.

Let the bread cool in the pan for 15 minutes before transferring it to a wire rack to cool completely.