Fresh Lemon Shortbread Bars (24 Squares)

Preheat oven to 163°C. Line the base and sides of a 23×33cm glass baking pan with parchment, leaving overhang for lifting.

Stir together 226g melted butter, 100g sugar, 2 tsp vanilla and 1/2 tsp salt, then incorporate 265g flour into a thick dough.

Press dough evenly into the pan, bake 20–22 minutes at 163°C until edges are lightly golden, then prick the hot crust with a fork without piercing all the way through.

Sift 400g filling sugar with 46g flour, then whisk in 6 eggs, 240ml fresh lemon juice and the optional 2 tsp zest until smooth.

Pour filling over the warm crust and bake 22–26 minutes at 163°C until the center is set, not jiggly. Verify the egg filling reaches at least 71°C.

Let cool after baking but move into the refrigerator within 2 hours, then chill for at least 1–2 hours. Avoid prolonged room-temperature storage of an egg dessert.

Lift out by the parchment, cut into 24 squares and dust with optional 1 tbsp confectioners' sugar; keep leftovers covered in the refrigerator.