Heat treat your flour by microwaving it in a bowl for around 1 -2 minutes or until it's hot, or pouring it on a baking sheet and baking it in a preheated oven (350°F) for 5 minutes, then set aside to cool* (SEE NOTES)
In a medium microwave-safe bowl, melt butter. Whisk in the sugars until the mixture is combined. Add in the vanilla extract.
Add in the flour, cocoa powder, and salt and mix.
Mix in the 3 tablespoon milk, then add more 1 tablespoon at a time until your desired consistency is reached.
Stir in the chopped chocolate or chocolate chips or other toppings and enjoy!
HEAT TREATING FLOUR: Flour is technically not completely safe to eat until it has been heat treated. Heat treat around ⅓ cup more flour than the recipe calls for, as there will be less flour in the bowl after it has been heated.MILK: You can use any kind of milk for this recipe! Start with 3 tablespoon of milk, then add in more milk until the batter is at your desired consistency.CHOCOLATE and ADD-INS: Feel free to get creative! I used mini dark chocolate chips and chopped chocolate, but you also add in sprinkles, crushed up Oreos, chopped peanut butter cups, peanut butter chips, white chocolate chips, or even chopped nuts.Storage Instructions: Brownie batter should be stored covered in the fridge for up to one week. It will be firm right out of the fridge. When you're ready to eat, let the batter soften at room temperature for around 20 minutes at room temperature.To freeze the batter, form it into a large ball or a few smaller balls. Wrap the dough in plastic wrap then place them in a ziploc bag and freeze for up to 2 months.