Heat treat the flour. Microwave the flour in a microwave safe bowl for three or four 30-second intervals, stirring in between or until flour reaches 165°F on an instant read kitchen thermometer. Alternatively, spread flour on a baking sheet and bake at 350°F for 5 minutes. Give flour a stir then set it aside for a couple of minutes to cool down.

In a large bowl or in the bowl of an electric mixer, cream the sugars and butter on medium until creamy and combined, about two minutes. Add the vanilla followed by the milk or heavy cream.

Turn the mixer on low and add the flour and salt until combined. Stir in the chocolate. Use your hands or a small cookie scoop to form the dough into small balls. Place on a plate and set aside at room temperature. 

For best results, place the bowl of your electric mixer in the freezer for at least 30 minutes before using. Add the ice cream to the bowl of your electric mixer fitted with the paddle attachment. Whip the ice cream on medium until creamy, about 30 seconds. Be careful not to overmix. Scrape down the sides of the bowl and add the chopped chocolate,  a few cookie dough balls, and a few tablespoons of the hot fudge sauce (if using)  into the ice cream. Turn the mixer on low and mix very briefly til just combined. 

Spoon some ice cream into the bottom of your glasses.* Break up a few of the cookie dough balls and sprinkle them over the ice cream. Drizzle some hot fudge sauce over top, if using. Continue layering and finish with balls of cookie dough or one big scoop of cookie dough! Enjoy immediately!