Ingredients:
- Shortbread Crust:
- 1 cup (226 g / 2 sticks) unsalted butter, softened
- 1/2 cup (60 g) powdered (confectioners') sugar
- 2 cups (250 g) all-purpose flour
- 1/4 teaspoon fine sea salt
- Lemon Filling:
- 4 large eggs, room temperature
- 2 cups (400 g) granulated sugar
- 1/2 cup (120 ml) fresh lemon juice (about 3–4 medium lemons)
- Zest of 2 lemons (about 2 tablespoons / 6–8 g), finely grated
- 1/4 cup (32 g) all-purpose flour
- 1/8 teaspoon fine sea salt
- Optional: 1–2 tablespoons unsalted butter, melted and cooled (for extra gloss)
- To Finish:
- Powdered sugar for dusting (optional) — about 2–3 tablespoons (15–20 g)
Instructions:
- Prep: Preheat oven to 350°F (175°C). Line a 9x13-inch pan with parchment leaving a 1–2 inch overhang on two sides; grease lightly.
- Make the Shortbread Crust: Cream the butter and powdered sugar until smooth. Mix in flour and salt just until combined; dough will be crumbly but holds when pressed.
- Press the dough evenly into the prepared pan (use the bottom of a glass for an even surface). Bake 15–18 minutes, or until edges are just turning golden — crust should be set but not deeply browned. Remove from oven; leave oven on.
- Make the Lemon Filling: While crust bakes, whisk the eggs and granulated sugar until combined and a bit frothy. Stir in lemon juice, lemon zest, flour, and salt until smooth and no lumps remain. Optional: stir in melted butter for extra sheen.
- Assemble & Bake: Pour the filling evenly over the hot par-baked crust. Return to oven and bake 20–25 minutes. Key doneness cue: edges should be set and slightly puffed; center should still have a gentle jiggle.
- Cool & Chill: Let cool on a wire rack to room temperature (30–60 minutes). For clean slices and best gooey texture, chill in the fridge 1–2 hours (or overnight).
- Finish & Serve: Use parchment overhang to lift slab from pan; dust with powdered sugar if desired. Slice into 24 bars using a sharp knife wiped between cuts. Serve chilled or at cool room temperature.