• Preheat oven to 325 degrees F.
• Add the butter, sugar, and vanilla into the bowl of a stand mixer and cream using the paddle attachment until light and fluffy, about 3 minutes. Add the eggs one at a time, scraping down the bowl as needed.
• In a separate bowl, combine the flour, baking soda and salt and whisk well, then add to the butter and egg mixture.
• Beat on low speed until well incorporated and no streaks of butter remain, but do not overmix.
• Line a 9" x 13" baking sheet with parchment paper, or lightly spray with nonstick cooking spray. Press the cookie dough into the prepared baking pan, covering the bottom of the pan as evenly as possible.
• Bake for 20-25 minutes, or until just barely golden. Remove from the oven and let cool completely.

Vanilla Buttercream Frosting

• In the bowl of a stand mixer, cream together the room temperature butter using the paddle attachment until light and fluffy.
• Add the milk and powdered sugar and mix on low speed until incorporated.  Add the vanilla extract and mix again on low until incorporated. Increase speed and beat until the frosting is fluffy and spreadable. You may need to add a bit more powdered sugar to adjust the consistency.
• Using an offset spatula, spread the frosting over the top of the cooled sugar cookie bars. Garnish the tops with your favorite Christmas sprinkles, then cut into bars. Enjoy!