Preheat your oven to 175°C (350°F). Line a 9x9 inch pan with parchment paper.
Cream the butter and brown sugar until fluffy. Add eggs, vanilla, ginger, and cinnamon. Mix well.
In another bowl, whisk flour, baking powder, and salt. Combine with the wet mixture.
Fold in chopped white chocolate and cranberries. Spread batter evenly into the pan.
Bake for 20–22 minutes, or until the edges are golden and the center is set. Let cool completely.
For the frosting, beat cream cheese with powdered sugar, orange zest, and vanilla until smooth.
Spread frosting over the cooled base. Sprinkle chopped cranberries and drizzle melted white chocolate on top.
Chill slightly for cleaner slicing. Cut into squares, then diagonally to make triangles.