Preheat oven to 375°F and line 2 large baking sheets with parchment paper or grease lightly with nonstick spray.
In a large mixing bowl, use a hand mixer to beat the Snickerdoodle cookie mix, large egg, softened butter, and sour cream together for 2-3 minutes, or until thoroughly combined.
17.9 ounces Snickerdoodle cookie mix, 1 large egg, ½ cup salted butter, 3 tablespoons sour cream
Fold in the white chocolate chips and dried cranberries until evenly distributed.
¾ cup white chocolate chips, ¾ cup dried cranberries
Using a 1½-inch cookie scoop, scoop out dough and form into even balls. Place them on the prepared baking sheets with 1 inch between each cookie.
Bake for 8-13 minutes or until the edges get golden brown. Do not overbake.
Remove from the oven and cool for 5 minutes before removing to a cooling rack or serving warm.