In a medium bowl, whisk together flour, baking powder, soda, and salt.
In large bowl, combine sugar, brown sugar and butter; beat until light and fluffy. Add egg and vanilla; beat well. Add flour mixture and mix just until blended. Add oats, Craisins, and white chocolate.
Cover with plastic wrap; refrigerate 30 minutes.
Bake at 375° for 8-12 minutes until the edges are golden brown, but the center is still soft. Cool on the baking sheet for 5 minutes and then remove to a wire rack to cool completely.