In the bowl of a stand mixer fitted with the paddle attachment, beat the butter, sugar, egg, vanilla and molasses together. (Alternatively, use a large bowl and electric hand mixer.)
Combine oats, flour, cinnamon, baking powder and salt in a separate bowl. With the mixer on low speed, slowly add the dry ingredients to the wet ingredients until combined. Fold in the cranberries and white chocolate morsels. Chill the cookie dough for at least 1 hour.
Preheat oven to 350 degrees. Line a cookie sheet with parchment paper.
Drop dough in heaping tablespoons onto prepared baking sheets, spacing them about 2 inches apart. Bake cookies 14-16 minutes until they are golden. Allow to cool at least 5 minutes on the baking sheet before transferring to a cooling rack.