Preheat oven to 350 degrees F. Spray a 6 cup muffin cup with cooking spray or grease it well.
Combine the buttermilk and bran cereal; let stand for 5 to 10 minutes or until cereal is softened.
Meanwhile, in a small bowl, stir together flour, baking powder, baking soda, cinnamon and salt; set aside.
Stir egg, brown sugar, maple syrup and oil into bran mixture. Add flour mixture to bran mixture; stir just until combined.
Spoon batter into prepared muffin cups and bake for 25 to 30 minutes or until a toothpick inserted in centers comes out clean. Cool in muffin pan on a wire rack for 5 minutes. Remove from muffin cups and cool completely.
Drizzle with Maple Icing. Maple Icing: In a small bowl, combine 1 teaspoon melted butter with 1/2 cup sifted powdered sugar and enough milk to make a drizzling consistency. Add 1/4 teaspoon maple flavoring and stir until smooth.