Preheat oven to 180ºC and line two baking trays with baking paper.
Place butter and sugar into TM bowl and cream 10 sec/speed 3.
Add egg and mix 10 sec/speed 3.
Add vanilla and milk and mix 10 sec/speed 3.
Add flour, bicarb and salt and mix 5 sec/speed 3.
Add oats and raisins (if using) combine 20 sec/Interval.
Bake 10-12 mins. Leave on tray for one minute before removing to a cooling rack.