I bake bread with them:
1.5 cups spent grain
3-4 cups flour (this will vary depending on how wet your spent grains are, mine are pretty dry, I BIAB and squeeze the heck out of them, 3 cups for me)
1 cup water (or cut back on the water if your grains are really wet)
3/4 tbs salt
1 pack or 1 tbs dried yeast
Mix the ingredients together and let rise to double size then punch it down knead and rise again. Punch down and form a round loaf allow it to rest while preheating the oven and Dutch Oven to 450 degrees.
Sprinkle corn meal or flour in the bottom of the Dutch Oven. Place loaf in Dutch Oven and Bake covered at 450 degrees for 30 minutes then uncovered for an additional 15 minutes.
The last one I made was from a Porter, it was great. The next time I bake bread from a Porter I’m going to add a little molasses.