2 c all-purpose flour
1/4 c sugar
1 Tbl baking powder
1/2 tsp salt
1 c milk
1 egg, beaten
1/3 c vegetable oil
3/4 c mashed banana
1/2 c chopped walnuts

Preheat oven to 400 F. Grease a 12 cup muffin pan. Sift flour, sugar, baking powder and salt into a medium bowl; make a well in center.
Mix milk, egg, oil, banana and walnuts in a small bowl. Pour mixture into well.
Mix batter just until moistened; do not overmix.
Spoon batter into prepared muffin cups. Bake until a toothpick inserted in center comes out clean or until muffins are golden brown, about 15 minutes.