Preheat the oven to 350 degrees F.
Beat together the shortening, butter, and add white sugar until light and creamy.
Mix in the egg, egg yolk, corn syrup, and vanilla extract.
Beat in the peppermint extract to taste.
Add in the flour, baking powder, salt and crushed candy canes. Mix until just combined.
Drop ball shaped spoonfuls onto baking sheet. Flatten out into a disc for even cooking.
Bake 2 inches apart on a parchment lined cookie sheet.
Bake 9-12 minutes.
*Its best to slightly under-baking the cookies, letting them cool most of the way
Beat together the softened butter, softened cream cheese, vanilla, and peppermint extract.
Beat in the powdered sugar, slowly adding about 1/2 a cup at a time until a smooth frosting is formed.
You can add a little milk if needed to thin your frosting to desired consistency.
Frost the cookies and add peppermint crunch sprinkles to the top.
Store in an airtight container at room temperature.