Preheat the oven to 190C/375F/Gas mark 5
Sift together the flours, spice and caster sugar. Stir in the bran and lemon rind. Rub in the butter and stir in the sour cream. Mix to a firm dough. Knead the dough on a lightly floured surface until smooth. Cover and refrigerate for 30 minutes.
Roll the dough between sheets of greaseproof paper to a 25cm x 30cm rectangle. Cut into 1 ½ cm strips crossways. Cut the strips in half to measure 12 ½ cm. Refrigerate for 15 minutes or until just firm.
Gently twist the strips. Sprinkle with combined extra bran and brown sugar. Place the strips about 1cm apart on greased baking trays. Bake for about 10 minutes or until lightly browned. Cool on the trays. Makes about 50.
