Thin and crispy chocolate chip cookies

Melt the butter over very low heat, using the minimum heat possible, and set aside to cool.

Measure the light brown sugar, white sugar and corn syrup into the mixer bowl.

With the paddle on medium, stream in the melted but not hot butter and mix three to four minutes until homogenous and lightly golden brown -- not creamed, since creaming makes a chewier softer cookie.

Add the egg yolk, vanilla extract and milk and mix 30 to 45 seconds on low.

Add the flour, salt and baking soda and mix on low about 30 seconds only; mixing further develops gluten and gives tough chewy cookies.

Add the chopped chocolate and the toasted walnuts and paddle briefly on low, then fold gently about 30 seconds.

Scoop chunks slightly smaller than a golf ball, six to a parchment lined sheet tray, without shaping them.

Bake straight away at room temperature rather than chilling, so the dough spreads more and bakes thinner and crispier.

Drop one or two chunks of chopped chocolate on each cookie and add a strong pinch of flaky salt.

Bake in a preheated 325F oven for 14 to 16 minutes.

Rest on the tray about five minutes to carry over cook; four to five minutes more in the oven if you want them crunchier.

Move to a wire rack to finish cooling and set their crisp.