Refrigerating the dough for 2 hours helps to firm up the butter so that the cookies do not spread while they bake.
If you’re not in a hurry, refrigerate the dough for at least 12 hours before baking. This will allow the dry ingredients to better absorb the humidity of the egg and butter.
Once the balls of cookie dough are frozen, transfer them to an airtight container. They will keep for 3 months in the freezer. You can bake them from frozen by adding 4 minutes to the cooking time, about 16 minutes.
