Preheat oven to 400x.
Make sure the oven rack is in the highest position.
Combine the flour, baking soda and salt in a bowl and set aside.
With mixer on low speed, combine the butter with white and brown sugars, egg yolk, vanilla extract and water. Increase the speed to high and beat until thoroughly mixed and light.
With a spoon, combine the creamed mixture with the dry ingredients. The batter may appear crumbly, but it will come together. Stir in the chocolate chips.
Using a heaping tablespoon as a guide, make 13 evenly sized balls and place 5 cm apart onto a cookie sheet.
Put the cookie sheet in the oven and immediately decrease the temperature to 350x. Bake for 5 minutes, then reverse the pan so that the back cookies are now in the front. Increase the temperature to 375x. Bake for 4-5 minutes longer; the cookies will appear golden brown with small pale centers. Cookies will complete cooking as they cool on the pan. This technique produces chewier cookies.
Cool the cookies on the pan for 2 minutes; remove to a rack to cool completely.
Yields a baker's dozen.