To prepare the cake base:

1. Preheat oven to 350 degrees F.
2. In a small bowl, combine the flour and confectioners sugar. Cut in the butter until the mixture is crumbly. Press the mixture into a greased 13×9-inch baking dish. Bake until the edges are light brown, about 20 minutes.
3. In the bowl of a stand mixer fitted with a paddle attachment, beat the cream cheese on medium speed until smooth. Reduce mixer speed to low. Add the milk and lemon juice, then pour over crust.

To prepare the filling:

1. In a small bowl, combine the cornstarch and brown sugar. Stir in the cranberry sauce until well combined.
2. Spoon the sugar-cranberry mixture evenly over the cream cheese layer.

To prepare the topping:

1. Preheat oven to 325 degrees F.
2. In a small bowl, combine the flour and brown sugar. Cut in the butter. Fold in the walnuts.
3. Sprinkle the topping mixture over the cranberry filling.
4. Bake until the topping is golden brown, about 40 minutes.
5. Transfer to a wire rack, and allow to cool completely.
6. Cover and refrigerate at least 3 hours before cutting into bars.