Preheat your oven to 350°F (175°C) and grease a 9x9 inch baking pan.
In a bowl, combine flour, oats, baking soda, cinnamon, and salt.
In a separate bowl, cream together butter, brown sugar, and granulated sugar until fluffy.
Beat in the egg and vanilla extract until well combined.
Gradually add the dry ingredients to the wet mixture, stirring until just combined.
Fold in the cranberries and white chocolate chips.
Spread the mixture evenly in the prepared pan.
Bake for 20-25 minutes until golden and a toothpick comes out clean.
Allow to cool completely in the pan.
In a bowl, mix cream cheese, powdered sugar, and vanilla until smooth, then spread over the cooled bars.