Sift the flours, salt, baking powder and baking soda.
Combine the butter and sugars in a bowl and mix for 2 minutes on medium speed until pale and light.
Stir in the eggs, one by one, then add the egg yolk and vanilla and mix well.
Add half of the flour mixture and mix on low speed for 30 seconds until incorporated.
Add the rest of the flour and chocolate and mix with a spatula until incorporated.
Drop spoonfuls of dough on a baking tray lined with baking paper. I prefer scaling all my cookies. I usually scale around 40g. Depending on the size you choose, this recipe will yield a different number of cookies.
Freeze the cookies for 1 hour at least then bake in the preheated oven at 350F for 12-14 minutes or until the cookies turn slightly golden brown on the edges.
When done, remove from the oven and gently press the cookies with a potato masher to even them up. This step is not compulsory, but I do love having them all looking flat and pretty much the same.
Allow to cool completely in the pan before serving.