In this picture, I used a party confetti cake mix, since that is what I had on hand.
1 cake mix
2 eggs, lightly beaten
1/2 C oil
1 tub favorite frosting
Preheat oven to 350. Combine cake mix, eggs, and oil and stir to mix well. Scoop dough and form into little balls, about 1" in diameter. Place dough balls onto ungreased cookie sheet. Bake approximately 8 minutes. Let stand 1 additional minute on pan before transferring to cooling rack. After cookies are cooled, pair up cookies by size. Spread frosting onto bottom of one cookie and use 2nd cookie to create the other half of the sandwich. Add sprinkles if desired.
Variations: For the holidays, use a yellow or chocolate cake mix. After making sandwiches roll the exposed frosting in crushed candy cane bits. For cookies and cream, use a chocolate or devil's food cake mix, white frosting and crushed oreo bits.