Preheat oven to 350 degrees
In a large mixing bowl, mix together the cake mix and baking powder.
In a small bowl, mix the eggs, oil, and vanilla extract.
Add the egg mixture to the cake mixture and stir until there are no cake mix white pockets. Make sure the batter is smooth and fluffy.
Fold in the sprinkles until combined and save a little extra for the topping.
With a mini ice-cream scooper or spoon, scoop the cookie dough onto a lightly greased cookie sheet 1 inch apart. Top each cookie with more sprinkles and bake for 9-12 minutes (they will likely look under-cooked but if the bottom is golden brown you're all set).
Place on cooling rack and let cool for 10 minutes. This is key to make sure the bottoms don't get too done. Enjoy each bite!