Sieve the all-purpose flour all together with baking soda and salt in a large bowl.
Take a mixing bowl and add the butter and caster sugar and mix on a medium speed until smooth and creamy.
Add egg to the creamy mixture and mix again for 30 to 45 seconds. Then add vanilla and mix well.
Finally, add flour into butter mixture gradually and mix well until combined with the help of a rubber spatula.
Now, add chocolate chips to the mixture and mix again.
Cover the cookie dough and refrigerate it for an hour.
Prepare the baking tray and align the parchment paper.
Now, take the cookie dough out of the refrigerator and scoop out and place on baking tray.
Bake the cookies for 15-18 minutes in a preheated (180oC) oven.
Remove the baking tray from the oven and place the cookies on the cooling rack.
You can enjoy these cookies immediately or store in anairtight jar.