These pumpkin muffins are a great alternative to the typical sweet, cake-like bakery muffin. They are moist and filling, made with whole wheat flour, wheat and oat brans, and flaxseed. The sweetness comes from banana, pumpkin puree, and a bit of brown sugar. Soaking the brans in buttermilk first is a key step to ensure the final muffins are moist, not dry.