Grease the pan. For easy removal of the bars, place parchment paper on the bottom and 2 sides of the pan. Grease again and then set aside. Preheat oven to 350°F. Mash the bananas and set aside as you prep the rest of your ingredients.
In a large bowl, add oil, vanilla, mashed bananas, brown sugar, and eggs.
1 cup mashed bananas, 1/2 cup oil, 1 tbsp vanilla, 2 eggs, 3/4 cups dark brown sugar
Add in the flour, baking powder, baking soda, cinnamon, and salt. Using a rubber spatula, gently fold it in until a soft batter forms. It will be runny.
2 cups flour, 1 1/2 tsps baking powder, 1/2 tsp baking soda, 1/2 tsp cinnamon, 1/2 tsp salt
Gently toss the blueberries in 1-2 tsps of flour before adding them into the mixing bowl. This will help absorb any liquid they may have from washing. Then add into the bowl and mix in a few times.
1 1/2 cups fresh blueberries
Transfer into the prepared pan and spread evenly.
Bake for 25-35 minutes. It really depends on your oven, but after 25 minutes I would start checking with a toothpick to see if it’s ready! A toothpick should come out clean.
Allow to cool, slice, and enjoy! This banana blueberry cake is soo good! It stays good on the counter for a day in an airtight container, and in the refrigerator for 5 days!