In the bowl of a stand mixer fitted with the paddle attachment, beat the cream cheese and butter until smooth, approximately 3 minutes.
8 ounces cream cheese, 8 tablespoons unsalted butter
Mix in the egg and vanilla extract.
1 large egg, 1 teaspoon pure vanilla extract
Add the salt and cake mix and beat on medium until smooth, about 1½ minutes.
15.25 ounces Dark Chocolate Fudge Moist Chocolate Cake Mix, ¼ teaspoon kosher salt
Refrigerate the dough for 1-2 hours, or until batter is firm enough to roll into balls.
When ready to bake, preheat oven to 350°F and line a baking sheet with parchment paper. Place the powdered sugar in a shallow bowl.
1 cup powdered sugar
Roll the chilled dough into 1-tablespoon-sized balls and roll the balls in the powdered sugar. Place the cookies 2-inches apart on the prepared baking sheet.
Once the oven has fully preheated, bake the cookies for 12 minutes (no longer). The cookies will look and feel a little wobbly and soft.
Place tray on a cooling rack to cool for 2 minutes, and dust the cookies with more powdered sugar (I use a mesh sieve).
Transfer individual cookies to the cooling rack to completely cool.
Dust with more powdered sugar, if desired.