Preheat the oven to 180C/350F/gas mark 4
Use a 900g/2 lb loaf tin.
Sieve together the flours, baking powder and mixed spice. Add any separated bran back to the mixture. Cream the margarine and sugar together. Stir in the soya milk, mashed banana and grated carrot, and fold this mixture into the sieved flour. Beat together and then place the mixture into the greased loaf tin. Sprinkle the sesame seeds on top. Bake for about I hour. Test with a warm knife. Turn out on a wire rack to cool.