1. Preheat the oven to 170ºC/Fan 150ºC/Gas Mark 3. In a small pan, place the butter, sugar and syrup, gently heat until melted. Remove from the heat and stir in the flour, oats, zest and juice then mix together to form a dough. Cool slightly.
2. Divide the mixture into 18-20 lumps, then roll each into a 10cm long 2cm wide sausage and place well apart on an oiled baking sheet. Flatten each slightly. Bake for 10-15 minutes or until pale golden. Cool slightly, then transfer to a wire rack to cool completely.