Preheat your oven to 375°F (190°C) and line a muffin tin with paper liners.
In a large bowl, combine the wheat bran and milk. Let it sit for 10 minutes to soften.
In another bowl, whisk together the flour, brown sugar, baking powder, and salt.
Add the oil, egg, and vanilla extract to the bran mixture and mix well.
Gradually add the dry ingredients to the wet mixture, stirring until just combined.
If desired, fold in raisins or nuts for added texture and flavor.
Spoon the batter into the prepared muffin tin, filling each cup about two-thirds full.
Bake in the preheated oven for 20-25 minutes or until a toothpick comes out clean.
Allow muffins to cool in the pan for 5 minutes before transferring to a wire rack.
Enjoy warm or store for later!