Preheat the oven to 350 degrees f(175 degrees).Grease 2 loaf pans.

Sieve the flour and salt in bowl add baking soda. Beat butter and sugar with an electric mixer in large bowl until its light and fluffy.

Add 1 egg per time allow to blend into the butter mixture add in the second egg beat Add the third n continue beating add the fourth egg along with vanilla extract. Beat mashed bananas thoroughly into a mixture.

Add flour mixture in small increment while beating until it combines into thick batter. Fold blue berries into the batter pour into prepared loaf pans. Bake in the preheated oven until when toothpick is inserted into the center comes out clean 30-35 minutes. Cool in pans for 10 minutes before removing to cool completely on a rack.