I also used a jar of vanilla frosting from Betty Crocker, which is also gluten free. Here's how I made these delicious oreo-flavored treats:
1. Mix up cake batter according to directions on package
2. Crush an entire package of Kinni-Toos cookies in a large ziploc bag with a rolling pin.
3. Add 1 1/2 cups crushed cookies to the cake batter, mix well, and spoon into muffin tins lined with paper liners.
4. Bake according to package directions.
5. Add 1/2 to 1 cup of crushed cookies to frosting and mix well. Frost cupcakes with frosting when cooled.
So easy, so easy to eat. They are so rich and chocolatey when they first come out of the oven. My kids loved these and I must say I was glad I froze them individually so that I couldn't eat the whole batch at once. But they didn't last the week...that 11-year-old found my stash and they were gone double time. Now that she's back in school I'll have to make some more. I may not even share this time.