Sift flour, baking powder and salt together in a bowl. Add bran and spices, and mix well. Beat eggs, sugar, oil and buttermilk together, in a second bowl. Add banana and stir. Make a well in the centre of the dry ingredients, and add the egg mixture, stirring roughly with a fork, without over-mixing.
Pour or spoon batter into lightly buttered muffin tray cups or individual muffin cases,