Combine bran cereal, bananas and yogurt in medium bowl. Let stand for couple of minutes to allow cereal to soften. Meanwhile, conbine flour, baking powder,baking soda,salt and nuts and/or raisins in a large bowl; set aside.

Stir eggs, sugar oil into bran mixture, then add to dry ingredients; stir just until combined

Spoon batter evenly into 12 greased or paper- lined muffin cups.

Bake in a preheated 400°F (200degrees C) until tops spring back when pressed, about 17 to 20 minutes. Let muffins cool in pan for a few minutes, then remove to a wire rack to finish cooling. Store in an airtight container