In a medium bowl add almond milk and vinegar. Stir. Then add wheat bran and stir again and let stand for 5 minutes.
In a large bowl add the flour, baking powder and baking soda, salt and walnut pieces and stir and make a well in the middle. Set aside.
Into the wheat bran bowl add the oil, molasses, splenda brown sugar, egg and vanilla and stir until well mixed. Then add this mixture into the bowl with the dry ingredients and mix just slightly just to moisten it (be careful not to overmix).
Pre-grease the muffin tins with a small amount of oil or use cooking spray. Fill the tins about 3/4 with the mixture.
Bake the full sized muffins for 20 - 25 minutes, and for the small size bake for about 17 - 20 minutes. After they are baked let stand for about 5 minutes then remove from pans.