In a large bowl, whisk together the sugars, salt, and butter until a paste forms with no lumps.
Whisk in the eggs and vanilla, beating until light ribbons fall off the whisk and remain for a short while before falling back into the mixture.
Sift in the flour and baking soda, then fold the mixture with a spatula. Be careful not to overmix.
Fold in the chocolate, then chill the dough for at least 30 minutes. For a more intense toffee-like flavor, chill the dough overnight.
Preheat oven to 350°F. Line a baking sheet with parchment paper.
Use a cookie scoop to scoop even rounds of cookie onto the parchment and bake for 12-15 minutes, or until the edges have started to barely brown.
Alternatively, weigh out 3 oz. of dough, make a round ball, flatten it slightly, and push a round chocolate wafer down onto the top.
Place onto parchment-lined baking sheet, leaving at least 4 inches of space between cookies.
Bake in preheated oven for 15-20 minutes, or until most of the cookie has browned.
Let it rest for a few minutes to firm and crisp up before enjoying.
