You can be relatively cavalier and experimental when it comes to chucking things into this cookie dough, but be aware that for this recipe 250g/9oz of additional ingredients is the limit ...
Cream the butter with the sugar in a free-standing mixer until pale ... Cover the bowl and chill for 1 hour (see Recipe Tips). Preheat the oven to 180C/160C Fan/Gas 4 and line 2 baking sheets ...