• Prepare the Crust
•  Preheat your oven to 350°F (177°C). Line a 9x13-inch baking pan with parchment paper, leaving overhang for easy removal, or grease the pan well.
• In a large mixing bowl, whisk together the flour, powdered sugar, and salt. Pour in the melted butter and stir until combined, the mixture will be crumbly.
  2 ½ cups all-purpose flour, 1/2 cup powdered sugar, 1/2 teaspoon salt, 1 cup butter
• Transfer the dough to the prepared pan, break it up, and press it into an even layer covering the entire bottom.
  
• Bake for 24-27 minutes, or until the crust is golden brown. Let it cool while you prepare the fillings.

Make the Cranberry Filling

• In a medium saucepan, combine the cranberries, granulated sugar, water, and lemon zest.
  12 ounces cranberries, 3/4 cup granulated sugar, 2 tablespoons water, 2 tablespoons lemon zest
• Cook the cranberries over medium heat until the berries burst and the mixture thickens, about 7-8 minutes.
  1 ½ cups granulated sugar, 1/2 cup all-purpose flour, 2 tablespoons lemon zest, 4 eggs, 2/3 cup lemon juice
  
• Let the cranberries cool while you prepare the fillings.

Make the Lemon Filling

• In a separate bowl, whisk together the granulated sugar, flour, lemon zest, eggs, and lemon juice until smooth.

Assemble and Bake

• Spread the cranberry filling evenly over the baked crust.
• Gently pour the lemon filling over the cranberry layer. Pour slowly to help keep the layers separate. A small amount of mixing is normal.
  
• Bake for 25–30 minutes, or until the lemon layer is mostly set but still jiggles slightly in the center when the pan is gently shaken.

Cool and Chill

• Let the bars cool completely to room temperature.
• Refrigerate for at least 3 hours to fully set.
• Once chilled, use the parchment paper to lift the bars from the pan. Slice into 12 squares.
• Dust with powdered sugar before serving, if desired.