I love the rainbow chip/funfetti cake mixes… so bright and cheery.  Instead of making a cake to bring to work, I opted to make cookie sandwiches and I used a brown sugar frosting as the filling.   

Cookies  – 1 funfetti or rainbow chip cake mix,  2 eggs, 1/3 cup oil.

Directions – preheat oven to 375.  Mix cake mix, eggs and oil.  Roll 2 tbs dough into balls.  Place on cookie sheet, lined with a nonstick baking liner.  I put 6 on each sheet.  Slightly flatten the cookies.  Bake 6 minutes.  Let cool completely.

Frosting/filling – 1/3 cup brown sugar, 1/3 cup butter, 3 tbs heavy cream, 1 1/2 cups powdered sugar

Cook brown sugar and butter over low heat until it boils.  Remove from stovetop.  Add cream.  Let cool 30 minutes.  Add powdered sugar.  You can add extra cream if you want to thin it out a little more.

Place frosting between cookies.  My cookies are on the large size, so I cut the cookie sandwiches in half.  You can make the cookies smaller if you want and make more of them.