http://www.vitalicious.com/
I found these on the site Hungry Girl and I really want to try them! You can get muffin tops, full muffins, and even brownies that are between 80 - 100 calories. And from what Hungry Girl has said, they're absolutely delicious and great for that sweet tooth! They even have sugar-free and low carb ones. The price isn't that bad either.
"Vitalicious provides you with:
100 calories
4-7g Fiber
4g Protein
Low-fat
Trans-fat free!
No Cholesterol
15 Vitamins and Minerals"
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I looked even further and you can purchase the mix for $6 and make yourself 12 muffins! Even better!