Preheat your oven to 350°F (175°C).
In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until smooth.
Beat in the egg and stir in the vanilla.
In a separate bowl, combine the flour, baking soda, and salt. Gradually add this mixture to the wet ingredients.
Stir in the dried cranberries and white chocolate chips.
On a baking sheet, drop a scoop of cookie dough using a small ice cream scoop, slightly press the dough, and leave some space.
Bake for about 10-12 minutes, or until the edges are lightly golden.
Let the cookies cool on the baking sheets for a few minutes before transferring them to wire racks to cool completely.