Preheat oven to 350 degrees F. Line two baking sheets with parchment paper.

In the bowl of a stand mixer, cream together the butter, oil, granulated and powdered sugars. Mix until mostly blended.

Sprinkle in baking soda, baking powder, and salt. Mix just quickly to distribute.

Add in sour cream, eggs, and vanilla extract. Mix well, about 2 minutes.

Slowly and gradually add in the flour while mixing on low. Mix well until a soft dough forms and cleans the sides of the bowl.

Using a spoon or spatula, stir in the sprinkles until evenly distributed.

Use a large cookie scoop (about 3-4 Tbsp) and roll the dough in to balls.

Add ½ cup granulated sugar to a shallow bowl and roll each cookie in sugar and place on a baking sheet spaced apart, only 6 cookies per pan.

Using the bottom glass or round measuring cup, dip the cup in sugar and press in to the cookie dough ball so each cookie is about ¼ to ½ inch thick. The edges with crack and the center will be flat.

Bake the cookies for 8 minutes until just set on the edges. Let the cookies cool completely before frosting.

Make the frosting by creaming together the butter, sour cream, and vanilla extract until fluffy, about 2 minutes.

Scrape down the sides of the bowl and add in the powdered sugar and milk. Mix well until thick, smooth, and creamy.

Spread frosting onto cookies evenly. Enjoy!