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.