Preheat your oven to 350°F (175°C) and lightly grease your baking sheets with butter or cooking spray.

In a medium mixing bowl, whisk together 2 ¾ cups of all-purpose flour, 1 teaspoon of baking powder, and ½ teaspoon of salt.

In a large mixing bowl, cream together ½ cup of softened butter, ½ cup of vegetable oil, and ½ cup of sour cream until smooth.

Add in 1 cup of granulated sugar and 1 teaspoon of vanilla extract, blending until well combined and fluffy.

Gradually add the dry mixture to the wet ingredients, mixing on low speed until a soft cookie dough forms.

Using a cookie scoop or your hands, portion out 2-inch balls of dough and place them onto the prepared baking sheets.

Bake the cookies for 10-12 minutes, or until the edges start to turn lightly golden.

Allow the cookies to cool on the baking sheet for about 5 minutes before transferring them to a wire rack to cool completely.

In a medium bowl, cream together ½ cup of softened butter, 2 tablespoons of milk, and 1 teaspoon of vanilla extract for the frosting.

Gradually add 2-3 cups of powdered sugar, mixing until smooth and creamy.

Frost each cookie with your colorful buttercream and add festive sprinkles on top.

Allow the frosted cookies to sit at room temperature until the frosting sets.