To Make The Cookie Dough
Beat the butter and sugar with an electric mixer until light and fluffy. Add in eggs and vanilla. Beat to combine. In a separate bowl, whisk together the flour, salt, and baking soda.
Add half of the dry ingredients to the wet ingredients and mix to combine. Add the sour cream and mix again. Add the remaining dry ingredients and stir until combined
Chill the dough for at least 6 hours, overnight is best.
To Bake The Cookies
Preheat oven to 325°F. Roll out about 1/3 of the cold dough to about 1/3-inch thickness on a well-floured surface. This is a sticky dough, so you will need to keep everything well-floured. Keep any dough that you are not working with in the refrigerator, so it will stay cold.
Bake the cookies for 9-11 minutes. Do not over bake them. They should still be pale when they come out of the oven. If the edges are browned, they won't be as soft.
Allow the cookies to cool on the cookie sheet for 1-2 minutes, before transferring them to a wire rack to cool. The cookies freeze well unfrosted. Allow them to cool completely before frosting.
To Frost The Cookies
Beat the butter with an electric mixer for 2 or 3 minutes, until fluffy. Slowly add the powdered sugar and continue beating. Add the vanilla and only enough of the milk or cream to make the frosting a spreadable consistency.
Use food coloring to tint the frosting with whichever colors you like. Frost the cookies and top with sprinkles, if desired.
Serving: 1cookie · Calories: 184kcal · Carbohydrates: 23g · Protein: 2g · Fat: 9g · Saturated Fat: 6g · Polyunsaturated Fat: 3g · Cholesterol: 32mg · Sodium: 139mg · Sugar: 13g