Preheat oven to 375°F (190°C).
Mash the bananas in a large mixing bowl until smooth.
Add almond or oat milk, melted vegan butter, and sugar to the mashed bananas. Mix well.
In another bowl, whisk together the flour, baking powder, and baking soda.
Gradually combine the dry ingredients with the wet mixture, stirring gently to avoid overmixing.
Fold in the blueberries carefully.
Pour batter into a greased or lined loaf pan.
Bake for 50-60 minutes, or until a toothpick inserted in the center comes out clean.
Let the bread cool in the pan for 10 minutes before transferring to a wire rack to cool completely.
