Poppy'S Favorite Cookies
["1/4 c. butter (softened)", "1 pkg. (8 oz.) cream cheese, softened", "1 egg yolk", "1/4 tsp. vanilla", "1 pkg. (18.5 oz.) cake mix (yellow, strawberry, any)"]
["Mix cream cheese and butter until blended.", "Blend in yolk and vanilla.", "Add cake mix (dry), 1/3 at a time, mixing well after each addition.", "If mixer is used, add last 1/3 by hand.", "Cover and chill for at least 30 minutes.", "Heat oven to 375\u00b0.", "Drop by teaspoons onto ungreased baking sheet. Bake 8 to 10 minutes or until light brown.", "Cool slightly before removing from sheet."]
["butter", "cream cheese", "egg yolk", "vanilla", "cake"]