In the bowl of a stand mixer fitted with the paddle attachment, cream the butter until light and fluffy, about 1 minute. With the mixer running on medium speed, add in the sugar and vanilla. Beat to combine, about 1 minute. Scrap down the sides of the bowl and then slowly add in the flour, with the mixer running on low. Beat until a soft dough is formed. Remove dough from the bowl and wrap tightly in plastic wrap. Refrigerate at least 2 hours. (The longer you refrigerate the less your cookies will spread.)

Remove your cookies from the fridge (the dough will be very hard) and preheat your oven to 300 degrees. Split your dough ball into small tablespoon size pieces. Roll each piece into a ball and then use your thumb to make an indentation in the ball. Work quickly because you don't want your dough to get warm. Fill each indentation with a teaspoon of cherry pie filling. Bake cookies 18-20 minutes or until set, but not brown. Shortbread tastes best when still a little soft.

Remove cookies from the oven and let them cool completely. Wait at least half an hour to glaze.

To prepare the glaze, whisk together the sugar, milk, and vanilla until smooth. Use a spoon to drizzle glaze onto the cookies.

Cookies can be stored at room temperature or you can freeze them for later! Enjoy!