preheat oven to 375 degrees, Spray large size muffin tin (6 muffins) with cooking spray
Mix together wheat bran and butter milk and let stand for about 10 minutes
beat together oil,egg,sugar, and vanilla, and add to the buttermilk/bran mixture
sift together twice the flour,baking soda, baking powder and salt,
stir flour mixture into buttermilk mixture, until just blended.
fold in raisins.
Spoon into prepared muffin tin
Bake for 15-20 minutes or until toothpick inserted into center comes out clean.