Preheat oven to 375 degrees. Line baking sheets with parchment paper. Set aside.
Beat together butter and brown sugar until smooth. Add in eggs, one at a time. Mix until combine.
In a large bowl. combine 1 1/2 cup oats, 1 1/2 cup flour, 1 tsp baking soda and 1 tsp salt. Stir to mix.
Gradually add flour mixture into butter mixture. Let each addition incorporate before adding more. Fold in 2/3 cup cranberries and 2/3 cup white chocolate chips.
Drop by 1 Tbsp amounts onto prepared baking sheets. Bake in preheated oven for 8-10 minutes or until lightly golden on top. Let cool for 1 minute on cookie sheet before transferring to wire cooling rack to cool completely.
(Optional) In a small bowl, add 1 cup white chocolate chips. Microwave for 1 minute at 50% power. Stir until smooth. Drizzle white chocolate over cooled cookies.