Begin by switching on the oven and heating it to about 190°C (gas mark 4-5).
Mix together the butter and caster sugar until the mixture is a smooth creamy paste, then add the brown sugar and mix in.
Lightly beat the egg, then blend into the mixture and add the vanilla extract.
Stir in the flour until it is thoroughly mixed, then add the chocolate chips.
The mixture should be firm enough to gently roll into balls in your hands – either use a cookie cutter for neat edges, or make your own round circles! The mixture should make about 24 cookies – plenty for all the family!
Pop your cookies on a baking tray (a piece of greaseproof baking paper is a good idea here) and bake for about 10 minutes, or until golden-brown. Leave the cookies to cool on a rack before enjoying!