Preheat oven to 350℉ (177℃). Line two baking sheets with parchment paper.
Beat sugar, butter, and oil, in a large mixing bowl for 2-3 minutes until creamy and light. Add sour cream and vanilla, then mix well to combine. Stop to scrape the bottom and sides of the bowl.
1 ½ cups (300g) granulated sugar, ½ cup (115g) salted butter, ½ cup vegetable oil, 1 cup sour cream, 2 teaspoons vanilla extract
Add flour, baking powder, salt, and Andes Peppermint Baking Chips, then mix on low speed just until combined, stopping to scrape the bottom and sides of the bowl.
4 ½ cups (635g) all-purpose flour, 1 teaspoon baking powder, 1 teaspoon salt, 1 (10-ounce) bag Andes Peppermint Crunch Baking Chips
Use a 2 1/2-inch cookie scoop to scoop balls of dough (about 3 to 4 tablespoons per cookie) onto the parchment-lined baking sheets or roll dough into golf-ball size mounds and space them a few inches apart.
Spray the bottom of a glass cup with cooking spray, then dip in about 1/4 cup of additional granulated sugar. Use the cup to press down on the top of each cookie, twisting as you do so, to flatten the cookies slightly. The twisting motion is what will give the cookies their jagged edges. Continue to dip the bottom of the cup in the sugar and repeat for each cookie, spraying the bottom of the cup with cooking spray as needed so the sugar sticks.
Bake for 12-15 minutes until the edges are just starting to brown slightly and the centers are set. Remove from the oven and cool completely. Chill until ready to frost.