Preheat oven to 350 degrees.
In a small bowl, mash three bananas with a fork. Set aside.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, cream together the softened butter and sugar until creamy.
Now add in the bananas, lemon zest, and lemon juice to the butter and sugar bowl and mix by hand.
Now add in the flour and mix by hand until just combined. Don't over mix!
Gently fold in the blueberries.
Spray a bread pan with cooking spray and pour in the batter. Top with extra blueberries.
Bake for 1 hour (or until knife comes out clean) MAKE SURE TO COVER WITH FOIL ONCE IT STARTS TO TURN GOLDEN ON TOP - for me it was 20 minutes into cooking.
Let cool for 1 hour before taking out of pan and slicing.