Using a handheld or stand mixer fitted with a paddle attachment, cream butter and oil until smooth on medium speed. Beat in sugars. Add egg and egg yolk and vanilla, then beat on medium-high speed until combined.
Beat in flour, vanilla pudding, salt, corn starch and baking powder.
Hand stir in white chocolate chips, sprinkles and broken up animal cookies.
Refrigerate for one hour.
Preheat oven to 350°F. Line 2 large baking sheets with parchment paper or silicone baking mats.
Roll into balls about an inch in diameter and place on baking sheet. Bake for 10-12 minutes. Check after 10 minutes to see if they are done.