Preheat your oven to 350°F (175°C). Grease a 9×5-inch loaf pan.
Using a fork, mash the bananas. You can also use a stand mixer to mash them.
In a large mixing bowl, beat together the granulated sugar, butter, egg, and vanilla extract until smooth and well combined.
In a separate large bowl, whisk together the all-purpose flour, baking powder, and salt.
Gradually stir the dry ingredients into the wet mixture, alternating with the milk and mashed bananas. If you want to add extra texture and flavor, fold in any optional mix-ins like walnuts or chocolate chips.
Pour the banana bread batter into the greased loaf pan and smooth the top with a spatula for an even finish.
Bake for about 1 hour, or until a toothpick inserted into the center of the bread comes out clean with just a few moist crumbs attached.
Let the banana bread cool in the pan for about 30 minutes. Then, carefully remove it from the pan and transfer it to a wire rack to cool completely.