01 -
Preheat oven to 350°F. Spray a 9×5-inch loaf pan with floured cooking spray, or grease and flour the pan, and set aside.
02 -
In a large bowl, add the egg, light brown sugar, oil, granulated sugar, sour cream, and vanilla. Whisk to combine.
03 -
Add 1 1/4 cups flour, baking powder, baking soda, and salt to the wet mixture. Stir until just combined, being careful not to overmix.
04 -
Add the mashed bananas and grated zucchini to the batter, stirring gently to combine.
05 -
In a medium bowl, toss the blueberries with 1/4 cup flour to prevent them from sinking while baking.
06 -
Add the floured blueberries along with any remaining flour bits into the batter. Stir until just combined, being careful not to overmix.
07 -
Pour the batter into the prepared pan, smoothing the top with a spatula. Optionally, sprinkle additional blueberries on the surface for a pop of color.
08 -
Place the loaf pan on a baking sheet to catch any overflow. Bake for approximately 90 minutes, checking for doneness at the 75-minute mark. Tent the pan loosely with foil at the 45-minute mark to prevent overbrowning. Rotate the pan occasionally during baking to ensure even cooking. The bread is done when the top is golden, the center is set, and a toothpick inserted comes out clean or with a few moist crumbs, but no batter.
09 -
Allow the bread to cool in the pan for 15 minutes before transferring it to a wire rack to cool completely. Slice and serve once cooled. Store at room temperature for up to 1 week or in the freezer for up to 6 months.