Preheat oven to 350F.
Spoon and level the all purpose flour in to a large bowl and stir in the baking soda, cinnamon, nutmeg and salt. Set aside.
Whisk together the unsweetened plant milk, apple cider vinegar and ground flaxseed in a separate bowl and set aside.
Mash the bananas and add to the plant milk mixture along with the vegetable oil, granulated sugar and molasses. Whisk well to combine.
Add the wet mixture in to the dry and stir until just combined. Be careful not to over mix.
Pour the batter in to the greased loaf pan and set aside.
Make the crumble by combining the sugar, flour and cinnamon in a small bowl. Then use a fork or clean hands to crumble the butter in to the sugar mixture until crumbles form.
Evenly spread the crumbles on top of the banana bread and bake for 50-55 minutes or until a toothpick inserted comes out clean or the loaf bounces back when gently pressed. Let cool before enjoying!