step 1
Preheat the oven to 190C/375F/Gas 5.
step 2
In a bowl, combine the flour, baking soda and salt.
step 3
In another bowl, beat the butter, sugars and vanilla extract until creamy. Beat in the egg. Gradually mix in the flour mixture. Stir in the chocolate.
step 4
Roll the dough into a sausage shape, about 5cm in diameter. Wrap it in cling film and keep in the refrigerator until ready to use.
step 5
When you are ready to bake the cookies, cut the dough into 2cm thick slices and lay on a baking tray, spacing them wide apart (they will spread to about 10cm in diameter). Bake for 9-11 minutes.