Combine the all purpose flour, baking powder, baking soda, and salt in a small bowl and mix well.
Beat the butter, brown sugar, and granulated sugar together with an electric mixer until well blended and somewhat fluffy.
Add the egg, then the vanilla extract.
Gradually add the flour mixture until thoroughly incorporated. The batter will be thick.
Mix in the dried cranberries and white chocolate chips with a spoon or spatula.
Wrap the dough in plastic wrap and chill in the refrigerator for at least an hour, or up to 3 days.
When you are ready to bake, preheat oven to 350°F.
Remove the dough from the refrigerator and let it sit at room temperature for about 10-15 minutes.
Roll the dough into 1-inch balls and place on a Silpat-lined baking sheet 2-inches apart. Flatten each ball of dough slightly and add more cranberries and chips to the tops, if desired.
Bake for 8-10 minutes, or until the bottoms are lightly golden.
Let cool for 5 minutes before removing to cooling racks.