Preheat and prep the pan: Heat your oven to 350°F (175°C).
Line a 9x5-inch loaf pan with parchment paper, letting some hang over the sides for easy lifting. Lightly grease the exposed sides.
Mash the bananas: In a large bowl, mash the bananas until mostly smooth with a few small lumps for texture. You should have about 1 1/3 cups.
Mix the wet ingredients: Add brown sugar, maple syrup, oil, non-dairy milk, and vanilla to the bananas.
Whisk until well combined and glossy.
Combine the dry ingredients: In a separate bowl, whisk the flour, baking soda, baking powder, salt, and cinnamon. This distributes the leavening evenly.
Bring it together: Add the dry ingredients to the wet bowl. Using a spatula, fold gently until just combined. Do not overmix; a few streaks of flour are okay.
Add the extras: Fold in any add-ins like nuts or chocolate chips.
Spread the batter into the pan and smooth the top. For a pretty finish, you can sprinkle a little sugar or lay a sliced banana on top.
Bake: Bake for 50–60 minutes, or until a toothpick inserted in the center comes out mostly clean with a few moist crumbs. If the top is browning too quickly, tent with foil for the last 10 minutes.
Cool properly: Let the loaf cool in the pan for 10–15 minutes, then use the parchment to lift it onto a wire rack. Cool completely before slicing for the cleanest cuts and best texture.
Slice and serve: Cut into thick slices.
Enjoy plain, spread with vegan butter, or drizzle with a little maple syrup.