Preheat oven to 350 degrees F. Line a 13x9" rectangular baking pan with foil, extending the edges of the foil over the sides of the pan. Spray the foil liberally with cooking spray; set aside.
In a large saucepan, melt the butter over medium-low heat. Remove from heat and stir in the brown sugar. Let cool for 5 minutes, then whisk in the eggs and vanilla. Lastly, add in the baking soda, salt, and flour until a thick batter forms. Fold in the dried cranberries and white chocolate chips.
Bake for approximately 20-25 minutes or until a toothpick inserted near the center comes out clean. Cool completely.
To make the frosting: Melt 1/2 cup of the white chocolate chips in a microwave safe bowl, about 15-20 seconds. Stir, then melt some more on low increments until melted. Add in the cream cheese and vanilla and use an electric mixer to combine on medium speed until creamy and combined. Beat in the confectioners' sugar, one cup at a time, until frosting is fluffy and light. Spread the frosting evenly over the bars and top with the dried cranberries.
Melt the remaining 1/2 cup white chocolate chips low and slow in the microwave. Drizzle evenly over the bars. Let set in the fridge for about 20 minutes before cutting into squares.