Preheat oven to 350°F. Prepare a 9 x 13-inch baking pan by lining it with a piece of parchment that slightly overhangs the edges.
In a medium bowl, whisk together the flour, baking powder, and salt.
In a large mixing bowl, cream the butter and shortening on high until smooth and well combined. Add the sugar and completely combine.
Add the eggs and vanilla and mix well. Add the flour mixture and thoroughly combine. Set aside 1 ¼ cups of the dough for the topping.
Press the remaining dough into the prepared pan. Bake for 12 minutes.
In a large bowl, combine the cranberries, granulated sugar, cornstarch, orange zest, orange juice, and vanilla. Mix well and evenly distribute the filling over the baked crust.
Place small dollops of the remaining dough over the cranberries.
Bake for about 35-40 minutes until the crust is golden brown. Set pan on a baking rack to cool completely before glazing.
In a small bowl, mix together the powdered sugar and the zest and juice of one orange. Adjust consistency with additional orange juice if needed.
Evenly distribute the glaze over the top of the bars. Lift bars out of the pan by the parchment and slice.
