Chop the nuts for the interlayer. It can be used to layer cookies or waffles. I have chocolate-covered waffles in my photo. They also need to be crushed, I did it with a knife. It is preferable to use nuts, because waffles and cookies get soaked over time and lose their "crispness", become tasteless. I.e. if you are going to serve dessert almost immediately, then fine, but if you plan to store it in the refrigerator - then, definitely, use only nuts!