In a large measuring cup, measure out ¼ cup of milk. Add in ¼ tablespoon of the white vinegar and stir. If you don’t have ¼ tablespoon just fill up ½ tablespoon about half way full. Let sit 5-10 minutes.
In a large bowl of an electric mixer fitted with the paddle attachment or using a hand held mixer, beat the softened vegan baking stick or butter and the dark brown sugar until soft and creamy. About 2 minutes.
With the mixer on low speed, slowly beat in the gluten free flour mixture a little at a time until just combined. Use a spatula to scrape down the sides and combine. Gently fold in ¾ cup chocolate chips using a spatula until combined.
Using a spatula, fold in ¾ cup (about 5-6 cookies) of broken chocolate sandwich cookies.
Only mix gently with the spatula until just combined. If you over mix, the batter with turn greyish. Chill the dough.
Take the dough out of the fridge and use an ice cream scoop to scoop the batter onto a clean plate. Pour the additional chocolate chips onto a plate. Press the top of each cookie into the chips.
Bake the cookies in the center rack of the oven at 325 degrees Fahrenheit for 13-15 minutes. Reshape press 3-4 sandwich cookie broken chunks into the tops of the hot cookies.