• Preheat the oven to 350 and line a baking sheet with parchment paper.

To make the cookies:

• In a medium bowl combine flour, and salt, mix until well incorporated.
  2 cups all-purpose flour, 1/4 teaspoon salt
• In the bowl of a stand mixer fitted with a paddle attachment cream butter and sugar.
  1 cup butter, 1/4 cup sugar
• Add in egg yolk and vanilla and continue mixing until well incorporated.
  1 egg yolk
• Add the flour mixture in gradually, mixing after each addition, until it is all added.
• Scoop out dough in tablespoon size scoops and roll into balls (or using a small cookie scoop)
• Place on the prepared cookie sheet.
• Using the handle of a wooden spoon, your finger, or another small round object press a hole in the center of each dough ball.
• Bake cookies for 8-10 minutes. Remove from the oven, gently press in the center of each cookie again.
• Place back in the oven and bake 10-12 minutes or until the cookie is light golden brown.
• Allow to cool on the baking sheet for 2-3 minutes before removing to a wire rack to cool completely.

For the Filling:

• In a medium bowl combine powdered sugar, corn syrup, vanilla and 2 teaspoons milk. Mix until well incorporated. If the filling is too thick add a little bit more milk ½ tsp at a time.
  1 cup confectioners sugar, 2 teaspoons milk, 2 teaspoons light corn syrup, 1/2 teaspoons vanilla extract
• Add enough green gel color until it's the perfect Grinch green color. You want it thin enough to scoop out but thick enough to set and not run out of the cookies.
  green gel food coloring
• Fill each cooled cookie with the filling, place a small red heart sprinkle in the center of each cookie.
  red heart sprinkles
• Allow the cookies to sit uncovered until the filling has set. Store in an airtight container.