I'm addicted to Vitatops which are 100 calorie muffin tops! They are found frozen in your grocery store because they have no preservatives. They retail for $5.50 for a box of just four muffin tops. I've tried them all and they're not created equal, I only like the chocolate and carrot cake flavors. The chocolate also comes in a sugar free version that is only available online. I searched through a few copycat recipes online and loved the one from the Dashing Dish. My muffins came out to 129 calories each, and that was because it's a whole muffin, not just a top since I don't have a whoopie pie pan. I do think these would taste better as just a muffin top because the chocolate chips are mostly on the top of the muffin so the top ends up being the best part. 

I used Hershey's Sugar Free Semi-Sweet Baking Chips which are made with Maltitol and taste just like regular chocolate chips! These muffins had a  lighter taste than a regular full fat/sugar muffin, but still good nonetheless! They only have 1 gram of sugar which comes from the natural sugar in apples. Instead of oatmeal I used Arrowhead Mills Organic Oat Flour which is just oatmeal grounded in a blender. I also use it to make protein bars. I used zsweet as my sweetener.