Preheat the oven to 350.

To make the crust: Mix the flour and brown sugar in a food processor until it is fully blended.

Add the butter pieces to the flour mixture and pulse the food processor until the butter is cut into tiny, pea-sized pieces and the dough looks lumpy.

Pour crust mixture evenly into an un-greased 9x13 baking dish. Press the crust down, with a spatula, to make it packed.

Bake crust in oven until golden brown, about 20 minutes.

In a medium bowl, use an electric mixer to beat the eggs until they are well blended.

Add the vanilla extract and 3/4 cup of the powdered sugar, then mix well.

Add the lemon juice and the rest of the powdered sugar. Mix until the powdered sugar is completely dissolved and then add the lemon zest.

As soon as the crust is finished, take it out of the oven and reduce the temperature to 300.

Immediately pour your lemon topping over the hot crust and continue to bake for 30 minutes.

Cool and cut into 24 bars.