Preheat oven 180°C. Using a mixer beat the butter and sugar until creamy. Add vanilla essence and 1 tbs each of orange and lemon rind. Beat in 3 egg yolks-adding them one at a time.

Beat in the milk and flour. Bring together on a lightly floured surface. If the mixture is too sticky adjust by adding a tbsp of flour at a time. Roll 1 tablespoon of the mixture into a 20cm log. Fold in half, pinch ends together and twist 2 times. You can also create “snail” shapes if you wish.

Place on a baking tray lined with non-stick baking paper. Whisk 1 egg yolk with 1 tbs water. Brush over the biscuits. Bake 15-20 minutes or until golden. Cool completely.