reheat your oven to 350°F (175°C). Grease a 9x5-inch loaf pan.
In a large mixing bowl, mash the ripe bananas with a fork or potato masher.
Add the melted butter and vanilla extract to the mashed bananas, stirring until well combined.
Sprinkle the baking soda and salt over the banana mixture and mix in.
Add the sugar and brown sugar to the batter and stir until well blended.
Gradually add the flour, mixing until just incorporated. Be careful not to overmix; a few lumps are okay.
Pour the banana bread batter into the prepared loaf pan.
In a separate bowl, prepare the Cinnamon Crunch Topping by combining the flour, brown sugar, and ground cinnamon.
Add the cold butter pieces and use your fingers or a fork to incorporate until the mixture resembles coarse crumbs.
Sprinkle the Cinnamon Crunch Topping over the batter.
Bake in the preheated oven for 60-7 minutes, or until a toothpick inserted into the center comes out clean.
Allow the banana bread to cool in the pan for 10 minutes, then transfer it to a wire rack to cool completely before slicing.
Slice, serve, and relish in the delightful combination of moist banana bread and a crispy cinnamon streusel top.