Preheat oven to 350 degrees. Grease a loaf pan or line with parchment paper. Set aside.
In large mixing bowl add mashed bananas, sugar, salt and egg. Stir well to combine. Drizzle in melted coconut oil, stirring constantly. Add the cinnamon and stir to combine.
Mix together the baking soda and water and then add to the other ingredients. Stir well.
Add the flour to the mixing bowl and stir until JUST moistened (over mixing will create a dense bread). Gently fold in the blueberries and stir JUST to combine.
Pour the batter into greased loaf pan.
For Streusel Topping
In a small mixing bowl, combine the flour, sugar and oatmeal.
Add melted coconut oil and stir well. Gently drop the topping all over the batter in the loaf pan.
Place the bread into the oven and bake for 50-60 minutes or until a toothpick or knife inserted in the center of the bread comes out clean.