For the Cupcakes:
Preheat oven to 350°F. Line 24 muffin cups with paper baking cups. Place one cookie in each cup.
Prepare cake mix. In the bowl of a stand mixer fitted with the paddle attachment, combine the cake flour, all-purpose flour, sugar, baking powder, and salt. Cut softened butter into 1/2 inch cubes and add a few cubes at a time until all of the butter is incorporated. Mixture will be crumbly.
Add the eggs one at a time, beating slowly. Pour in the milk and vanilla. Increase the mixer speed to medium and beat for 2 minutes until batter is smooth. Fold in the sprinkles.
Divide batter evenly over cookies in prepared muffin cups. Bake 15 - 20 minutes or until toothpick inserted in center comes out clean. Cool 5 minutes. Remove to wire rack to cool completely.
For the Frosting:
Beat shortening and butter with electric mixer until light and fluffy. Slowly add in vanilla extract and half of the powdered sugar.
Gradually add in the heavy cream (or milk), followed by the rest of the powdered sugar. Finally, fold in crushed Oreo cookies.
Place frosting in decorating bag fitted with large round tip. Pipe frosting on top of each cupcake. Top with sprinkles and maraschino cherries if desired.