1

Preheat oven to Gas Mark 4/180°C/350°F.

2

To make crust, mix flour and light brown sugar using a food processor until fully incorporated.

3

Toss butter into flour mixture and pulse to combine using short bursts of power until butter is cut into tiny pea-sized pieces and dough appears lumpy. Sprinkle crust mixture onto an ungreased 13 X 9 X 2-inch baking pan as evenly as possible; press down with a spatula to create a packed surface. Place crust in middle of oven and bake until golden, about 20 minutes.

4

Meanwhile, to make lemon topping, beat eggs in a medium bowl with an electric mixer until well blended. Add vanilla extract and 3/4 of icing sugar; mix well. Add lemon juice and remaining icing sugar; mix until icing sugar is completely dissolved and then add zest.

5

As soon as crust us finished, remove from oven and reduce oven temperature to Gas Mark 2/150°C/300°F. Immediately pour lemon mixture over hot crust. Bake completely; cool, and cut into 24 bars.