How to Make It
Heat oven to 375° F. Coat a standard 12-cup muffin tin with butter (or cooking spray, if desired). Whisk together the flour, wheat bran, sugar, sunflower seeds, salt, cinnamon, baking powder, and baking soda in a large bowl. In a separate bowl, whisk together the banana, eggs, milk, vanilla extract, and butter.
Add the wet ingredients to the dry ingredients and whisk until combined and evenly moistened (do not overmix). Fold in the blueberries.
Divide among the muffin cups. (The batter should come up to the rim of each cup.) Bake, rotating once, until a toothpick inserted in the center of a muffin (avoiding a blueberry if possible) comes out clean, 25 to 30 minutes. Let cool for 5 minutes in the pan, then transfer to a wire rack. Serve warm or at room temperature.