Prepare the flax egg by mixing 1 TBSP of ground flax in 2.5 TBSP of boiling water. Set aside to rest.
Preheat the oven to 190°C(374°F). Prepare a muffin baking tray by lightly covering it with oil.
In a large mixing bowl, combine the brown bread flour, sugar, baking powder, baking soda, cinnamon, raisins, and salt.
In a small mixing bowl, stir the soy milk, banana, vanilla extract, and flax egg until combined.
Add the wet ingredients to the dry ingredients and stir with a spatula until well combined, without over stirring.
Pour the batter into the muffin tray and bake for 20-30 minutes or until a toothpick inserted into the centre comes out clean and dry.