Preheat the Oven:
Preheat your oven to 350°F (175°C). Grease a 9×5-inch loaf pan with butter or non-stick spray, or line it with parchment paper for easy removal.

Mash the Bananas:
In a large mixing bowl, peel the bananas and use a fork to mash them until smooth. It’s okay if there are some small lumps for added texture. You’ll need about 1 1/2 cups of mashed banana, which is roughly 3 ripe bananas.

Mix the Wet Ingredients:
Add the melted butter, granulated sugar, eggs, and vanilla extract to the mashed bananas. Stir until the mixture is smooth and well-combined.

Combine the Dry Ingredients:
In a separate bowl, whisk together the flour, baking soda, salt, and ground cinnamon.

Add Dry to Wet Ingredients:
Gradually fold the dry ingredients into the banana mixture. Stir gently until everything is just combined. Avoid overmixing to prevent a dense loaf.

Make the Cinnamon Crumb Topping:
In a small bowl, combine the flour, brown sugar, and cinnamon. Add the cold cubed butter and use your fingers or a pastry cutter to work the butter into the dry ingredients until it forms coarse crumbs.

Prepare the Pan:
Pour the banana bread batter into the prepared loaf pan, spreading it evenly with a spatula.

Add the Crumb Topping:
Sprinkle the cinnamon crumb topping evenly over the banana bread batter.

Bake:
Place the pan in the preheated oven and bake for 60-70 minutes or until a toothpick inserted into the center comes out clean. The topping should turn golden brown and slightly crisp.

Cool and Slice:
Let the bread cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely. Slice into thick pieces once cooled and enjoy!