preheat oven to 375.
Add the spent grain to a food processor, process until about 1/3 as course as before.
Add spent grain to a large bowl, stir in remaining ingredients. If the dough is too moist to stick together, add additional flour.
Using your hands, make 2 inch wide by 1/2 inch high disks.
Place on a cookie sheet that has been covered with parchment paper.
Bake at 375 for 25 minutes. Immediately pull the parchment paper and the cookies off the hot cookie sheet onto a flat surface, allow to cool.