Ingredients:
- For the Shortbread Crust: 2 cups (250 g) all-purpose flour
- For the Shortbread Crust: 1/2 cup (60 g) powdered (confectioners') sugar
- For the Shortbread Crust: 1 cup (226 g) unsalted butter, cold, cut into small cubes
- For the Shortbread Crust: 1/4 teaspoon fine sea salt (omit if using salted butter)
- For the Lemon Filling: 4 large eggs, room temperature
- For the Lemon Filling: 2 cups (400 g) granulated sugar
- For the Lemon Filling: 1/3 cup (44 g) all-purpose flour
- For the Lemon Filling: 1/2 cup (120 ml) fresh lemon juice (about 3–4 medium lemons)
- For the Lemon Filling: Zest of 2 lemons (about 2 tablespoons / 8–10 g)
- For the Lemon Filling: 4 tablespoons (56 g) unsalted butter, melted and cooled slightly
- For the Lemon Filling: 1/4 teaspoon fine sea salt
- For Finishing: 1/2 cup (60 g) powdered sugar for dusting (or to taste)
Instructions:
- Preheat oven to 350°F (175°C). Line a 9 x 13-inch (23 x 33 cm) rimmed baking pan with parchment paper leaving a 2–3 inch overhang on two opposite sides; lightly grease the parchment.
- Make the crust: combine 2 cups (250 g) flour, 1/2 cup (60 g) powdered sugar, and 1/4 teaspoon salt in a bowl or food processor. Cut in 1 cup (226 g) cold cubed butter until mixture resembles coarse crumbs with pea-size pieces. Press evenly into prepared pan; optionally chill 10–15 minutes.
- Par-bake the crust: bake 15–18 minutes, or until edges start to turn golden and center looks set. Remove from oven and let cool slightly while preparing the filling (keep oven on).
- Make the lemon filling: whisk together 4 large eggs and 2 cups (400 g) granulated sugar until smooth and slightly pale. Add 1/3 cup (44 g) flour and 1/4 teaspoon salt; whisk until no lumps remain. Whisk in 1/2 cup (120 ml) fresh lemon juice, zest of 2 lemons, and 4 tablespoons (56 g) melted butter until glossy and combined.
- Assemble and bake: pour the lemon filling over the warm crust and spread gently to an even layer. Bake at 350°F (175°C) for 22–27 minutes — edges should be set and golden while the center remains noticeably jiggly (about 2 cm of movement when gently shaken).
- Cool and finish: remove from oven and cool on a rack at room temperature for at least 1 hour. For cleaner slices, chill 1–2 hours until firm. Lift bars using the parchment overhang, dust with powdered sugar, and cut into squares.
- Store: keep in an airtight container in the refrigerator for up to 4–5 days. Bring to room temperature briefly before serving if desired.