Preheat oven to 190°C. Line two large baking sheets with parchment paper or lightly grease with baking spray.
In a large mixing bowl, beat Snickerdoodle cookie mix, large egg, softened butter, and sour cream using a hand or stand mixer for 2 to 3 minutes until a homogeneous dough forms.
Gently fold in white chocolate chips and dried cranberries until evenly distributed throughout the dough.
Using a 4-centimetre cookie scoop, portion dough into even balls. Arrange on prepared baking sheets, leaving 2.5 centimetres between each cookie.
Bake for 8 to 13 minutes or until edges are golden brown, taking care not to overbake.
Remove from oven and let cookies cool on baking sheets for 5 minutes before transferring to a wire rack. Serve warm or at room temperature.
Notes
For a more intense flavor, consider adding a pinch of sea salt to the dough.
Store cookies in an airtight container to maintain freshness.
These cookies are great for gifting during the holiday season.