1.Preheat oven to 100°C (160°C fan-forced). Line large oven trays with baking paper.
2.Beat butter, extract and sugar in a large bowl with an electric mixer until light and fluffy. Stir in the walnuts and flour.
3.Roll level tablespoons of dough into balls; place about 5cm apart on prepared trays. Bake for about 12 minutes or until biscuits are pale golden. Cool for 2 minutes.
4.Gently roll biscuits in sifted extra icing sugar. Place on wire racks to cool.
5.Dust again with sifted icing sugar just before packaging or serving.
Suitable to freeze. Not suitable to microwave.Note