4 oz (110 g) semi-sweet chocolate chunk, or milk chocolate
4 oz (110 g) dark chocolate chunk, or your preference
whole milk, to drink, optional
Preheat oven to 350°F (180°C).
In a large bowl, whisk together the sugars, salt, and butter until a paste has formed with no lumps.
Whisk in the egg and vanilla, beating until light ribbons fall off the whisk.
Sift in the flour and baking soda, then fold the mixture with a spatula, being careful not to overmix too much. This will cause the gluten in the flour to toughen which will result in cakier cookies.
Fold in the chocolate chunks evenly, then chill the dough for at least 30 minutes. For a more intense toffee-like flavor and deeper color, chill the dough overnight. The longer the dough rests, the more complex its flavor will be.
Scoop the dough with an ice-cream scoop onto a parchment paper-lined baking sheet, leaving at least 4 inches (10 cm) of space between cookies and 2 inches (5 cm) of space from the edges of the pan so that the cookies can spread evenly.
Bake for 12-15 minutes, or until the edges have started to barely brown.
Cool completely, and serve yourself a glass of milk.