Line a 15x10 jelly roll pan or rimmed cookie sheet with parchment paper.
Beat together melted butter and brown sugar over medium speed with an electric mixer.
Add in eggs, orange zest, 1 tsp orange oil, 1 tsp vanilla extract, and 1 tsp of the orange Cointreau which was drained from the dried cranberries;
Beat until mixed well. Sift spices, baking powder, salt, and flour together. Add to mixture and beat together until just blended. Do not over-mix.
Stir in white chocolate chips and cranberries by hand.
Spread evenly into the bottom of pan lined with parchment paper. Bake in preheated oven for 22-24 minutes, until set and golden brown at the edges. Do not over-bake or bars may be hard or tough.
Remove from oven and plac epan on a wire rack to cool. Allow bars to cool completely before topping with frosting.
Remove from oven and place pan on a wire rack to cool. Allow bars to cool completely before topping with frosting.