Preheat the oven to 350 degrees F. Spray a 13x9-inch baking dish with nonstick spray.
PREPARE THE BLONDIE LAYER:
In a medium bowl, melt the butter for one minute in the microwave; stir in the brown sugar. Scrape the butter and sugar into a large bowl and let cool to room temperature. Use an electric mixer to beat in the eggs and vanilla. In a separate bowl, whisk together the flour, baking powder, salt and cinnamon; gradually add the dry mixture to the butter mixture. Stir in the cranberries and chopped chocolate (the batter will be thick).
Spread the blondie batter into the prepared pan. Bake for 18 to 21 minutes, or until a toothpick inserted near the center comes out clean (do not over bake). Cool completely on a wire rack.
PREPARE THE FROSTING:
In a large bowl, use an electric mixer to beat the cream cheese and powdered sugar until well-blended. Gradually add half of the melted white chocolate; beat until blended. Frost the blondies. Sprinkle with cranberries. Drizzle with remaining melted white chocolate. Cut into 30 bars- square or triangle-shaped. Store in the refrigerator until ready to serve.
Notes
If you'd like to add an orange flavor to these bars, add 1 tablespoon grated orange zest to the frosting.