Make the cookies:

• Using a stand mixer with a paddle attachment, cream together the shortening and sugars. 1 cup shortening, 1 cup granulated sugar, 1/2 cup brown sugar
• Add the buttermilk, vanilla and egg. Mix again, on low speed, so it does not splash. Mix until combined, scraping the sides of the bowl as needed. The mixture will not be smooth and that's ok. 1 cup buttermilk, 1 teaspoon pure vanilla extract *, 1 large egg
• In a small bowl, whisk together the flour, baking powder, baking soda and salt. 4 3/4 cups all-purpose flour, 2 teaspoons aluminum free baking powder, 1 teaspoon baking soda, 1/2 teaspoon salt
• Add the flour mixture to the shortening/sugar mixture. Mix on low speed until combined. Stop the mixer to scrape the sides and the bottom of the bowl a few times during mixing to ensure it all gets incorporated together.
• Once the cookie dough is well mixed, move the dough to a glass bowl. Cover the bowl with plastic wrap and place it in the fridge to chill overnight.
• Preheat the oven to 350º Fahrenheit. Sprinkle a pastry mat with flour. The dough will be sticky so you want to be sure the pastry mat is well floured so the dough doesn't stick. I use about a total of 1/2 cup more flour when rolling.
• Divide the dough in half and roll out one-half of the dough on the floured surface, sprinkling flour on top of the dough as needed.
• Cut out the dough in the shapes you'd like. Place the cookies on a nonstick baking mat. Bake the cookies for 9-10 minutes, removing them before they are browned.
• Repeat with remaining dough, rerolling as needed. Allow the cookies to cool on a wire rack.
• Once the cookies are cool, frost them with buttercream frosting and sprinkles, if desired. Store in an airtight container. vanilla buttercream, sprinkles