Preheat oven to 350 degrees F. Spray a 9×5-inch loaf pan with nonstick spray.
Whisk the first four ingredients (dry) into a small bowl. Set aside.
In a large bowl, use an electric mixer to beat the butter until creamy. Then beat in the sugar until light and fluffy. Add the eggs, beating in one at a time. Stir in the dry ingredients and then banana.
Carefully stir in the blueberries.
Pour the batter into the prepared pan and bake for 50 minutes. A toothpick inserted into the center should come out clean.
Let the bread sit for 15 minutes, then remove it from the pan to a wire rack to cool.