In a large mixing bowl, cream together 3/4 cup of unsalted butter with 1/2 cup granulated sugar and 1/2 cup light brown sugar until the mixture is light and fluffy.

Beat in 1 egg and 1 teaspoon pure vanilla extract until fully incorporated.

In a separate bowl, whisk together 2 cups of all-purpose flour, 1 teaspoon of baking powder, and 1/4 teaspoon of salt.

Gradually add the dry mixture to the wet ingredients, mixing until just combined.

Set aside 2 cups of this dough for the topping.

Line an 8x8 baking pan with parchment paper and pat the remaining dough evenly into the bottom.

Preheat your oven to 350°F (175°C) and bake the crust for 15 minutes.

In a bowl, combine 2 cups of fresh cranberries, 1/2 cup granulated sugar, 1 tablespoon cornstarch, the zest of one orange, 1/4 cup orange juice, and 1 teaspoon vanilla extract.

Pour the cranberry mixture over the warm crust and crumble the reserved dough over the filling.

Return the pan to the oven and bake for an additional 40-45 minutes.

Let the bars cool in the pan on a wire rack for at least 1 hour.

Mix 1 cup of powdered sugar with a bit of milk or a dairy-free alternative until smooth for glazing.

Once cooled, slice them into squares and drizzle glaze over the bars before serving.