The ingredients were a bit surprising. It called for BLACK BEANS. The rest of the ingredients were expected. One of the things I would suggest is to REALLY MIX the ingredients well. I had a few whole beans in the muffin I ate and a bean is not something you expect to find in a muffin. I am not sure if the muffin with have the beany side effects... but with the taste, I am ok with destroying the world's atmosphere a tad.
I would suggest anyone who is interested in cooking with protein to look at the author's web page www.proteinpow.com for a ton of recipes and ideas. The page also has links to buy the harder to find ingredients.
Another issue I encountered was the chocolate protein powder I ended up using which was one that I had rejected in shake form because of the artificial sweetener taste. The taste was still there after cooking. So, the recipe can only get better with better chocolate whey protein powder. I topped my muffin with a Almond Coconut Butter type "frosting". It was rather drippy as Almond Coconut Butter normally is. This may be something that could be mixed with a thickening agent before frosting with it.
Overall, easy and delicious and only 82 calories per muffin, 8 g protein and 6 g carbs and YUMMY!