A layer of cookie dough in between the chocolate chips. Most Oreo cookies have a layer of brownie in between the brownie chips, too. Brownies on top.
These cookies can be cut into squares, and the edges can be sliced, too, in different ways.
Chocolate chips. These can range from white chips to a variety of different colors, including pink, green, black, orange, red, and even blue.
They also vary in thickness, which is different, depending on what you put into them.
Other ingredients. These include fruits, nuts, and a lot of dairy products, such as cheese or milk. Some chocolate cookies are loaded with nuts.