Melt butter and mix in sugars. Leave to cool for 5 minutes.
Add eggs, baking powder, bicarbonate of soda, salt, cinnamon, nutmeg and vanilla. Then add flour. Once mixed, add the cranberries and oats and mix everything well. Drop by teaspoonfuls onto a greased baking tray.
Bake for 12 to 15 minutes.
Cool on baking tray for 2 minutes, before transferring to wire rack to cool.