In a bowl, add the following: 1 cup all-purpose flour, 1 cup wheat bran, ½ cup oat bran, 2/3 cup brown sugar, 1 teaspoon baking powder, 1 teaspoon soda, ½ teaspoon salt
Whisk together, making sure to break any brown sugar clumps that may be present. In a separate bowl combine the wet ingredients: 1 cup buttermilk, ½ cup light vegetable oil, 1 egg, ½ teaspoon vanilla extract Whisk those together. Pour into dry ingredients, and add; ½ cup raisins
Mix all together with a few quick strokes. Let sit for 5 minutes.
Preheat your oven to 375 degrees.
Prepare your muffin pan by either oiling the cups or using paper inserts. Evenly distribute the batter between the cups.
Bake for 15 minutes or until a toothpick inserted t the middle comes back clean. Let cool for 5 minutes then transfer to a cooling rack until ready to serve.