Preheat the oven to 180°C (170°C fan-forced).
Sift the self-raising flour and salt together and set aside.
Beat the butter, caster sugar and honey together until light and creamy.
Add the egg and beat into the mixture.
Add the mandarin zest and juice, beat until combined.
Add the sifted flour and fold into the butter mixture. Refrigerate the mixture for about 15 minutes. Roll the dough into logs 4cm in diameter and chill until firm.
When ready to bake, cut into 5mm thick rounds. Place, well-spaced, onto baking sheets lined with baking paper. Bake for 12 minutes or until light golden and slightly firm to the touch. Cool on a wire rack and dust with icing sugar.