Cream the butter by hand or in an electric mixer.

Add the sugar and continue creaming.

Beat in the eggs and vanilla.

In a separate bowl, mix together the flour, baking soda and salt.

Beat the flour mixture into the creamed mixture a bit at a time.

When the mixture is thoroughly blended, stir in the chocolate chips.

Take a large piece of waxed or greaseproof paper or baking parchment and sprinkle a little flour on it.

Take one third of the cookie dough and put it in the centre of the paper.

Using the paper to help you, shape the dough into a log about 8 to 10 inches long.

Wrap the dough up tightly in the paper or baking parchment.

Repeat with 2 more pieces of baking parchment and the remaining two-thirds of the dough.

Place the cookie dough logs in a plastic bag and put in the refrigerator for at least 6 hours or overnight. You can then either freeze the dough, or bake it from chilled. If you plan to freeze, remove the baking parchment and wrap the firm logs in cling film (Saran (plastic) wrap)

When you want to bake the frozen or chilled dough, preheat the oven to 350℉ (about 160℃ for a fan oven).

Slice the cookie logs into slices just a bit less than one quarter inch thick (about half a centimetre) and place on baking sheets about an inch apart.

Bake the cookies for 8 to 10 minutes from chilled (or 12 to 13 minutes from frozen) until they are just starting to turn lightly golden. Be careful not to over-bake.

Remove the baking sheets from the oven and leave the cookies to cool on the baking sheets for five minutes.

Carefully remove the cookies from the baking sheets and cool on a wire rack.