Preheat your oven to 350°F (175°C). Grease and line an 8x8-inch baking pan with parchment paper, allowing the edges to hang over for easy removal.
In a small bowl, whisk together the flour, baking powder, and salt. Set aside.
In a large mixing bowl, cream the softened butter and brown sugar together until light and fluffy.
Beat in the egg and vanilla extract until well combined.
Gradually add the dry flour mixture to the butter mixture, stirring until just combined. Do not over-mix.
Fold in the orange zest, chopped dried cranberries, and white chocolate chips until evenly distributed.
Pour the batter into the prepared baking pan, spreading it evenly.
Bake for 20-25 minutes or until the edges are golden and the center is set (a toothpick inserted should come out clean). Let cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
Meanwhile, in a medium bowl, beat the softened cream cheese with powdered sugar and milk until smooth and creamy.
Once the bars are completely cool, spread the cream cheese frosting evenly over the top.
Garnish with additional chopped cranberries and orange zest for a festive touch. Cut into squares or bars.
Notes
Allow bars to cool completely before frosting for best results.