Combine flour, baking soda, baking powder, salt and cinnamon in a large mixing bowl.
Mash bananas. If you like pieces in your bread, don't mash them as fine. If not, mash well.
Combine brown sugar, coconut oil, yogurt, vanilla and mashed bananas in a separate bowl. Whisk until smooth.
Add the wet ingredients to the dry ingredients, stir just until combined.
Spray or grease a 9x5 inch loaf pan and pour mixture into it.
Sprinkle streusel topping evenly over the top.
Bake for 55-60 minutes or until a toothpick comes out clean.
Streusel Topping
Add the flour, brown sugar, and cinnamon in a medium bowl and mix until combined. Cut in the butter using a fork or a pastry blender, until it resembles coarse crumbs. Stir in chopped banana chips. Sprinkle evenly on batter.