Instructions:

1. Preheat the Oven:

• Preheat your oven to 350°F (175°C). Grease and line a 9×9-inch (23×23 cm) square baking pan with parchment paper, leaving an overhang on two sides for easy removal.

2. Make the Shortbread Base:

• In a mixing bowl, cream together the softened butter and powdered sugar until light and fluffy.
• Add the all-purpose flour, salt, and lime zest. Mix until just combined.
• Press the shortbread mixture evenly into the bottom of the prepared baking pan.
• Bake the shortbread in the preheated oven for about 15-20 minutes, or until it’s lightly golden brown around the edges. Remove it from the oven and let it cool slightly.

3. Prepare the Key Lime Filling:

• In another bowl, whisk together the granulated sugar, eggs, key lime juice, all-purpose flour, and baking powder until well combined.
• Pour the key lime filling over the baked shortbread base.

4. Bake the Bars:

• Return the baking pan to the oven and bake for an additional 20-25 minutes, or until the edges are set, and the center is just slightly jiggly.

5. Cool and Serve:

• Allow the Key Lime Shortbread Bars to cool in the pan on a wire rack.
• Once cooled, refrigerate the bars for at least 2 hours or until well chilled. This will make them easier to slice.